Sonic the Hedgehog/WMG

Here's where you can find various theories concerning the Sonic universe. Add your personal theories to the folder they best fit.

Tails Doll is still alive and lives in Westopolis.
Many people think Tails Doll's theme is "Can You Feel The Sunshine" but if you have ever played Sonic R his actual theme is "Living in the City". The lyrics clearly say he's still alive in the city.

Every Shadow after Sonic Adventure 2 isn't the original.
The Shadow from every game after Sonic Adventure 2 is a fake because in every game he was in he had fangs, except Sonic Adventure 2. The fangs were clearly the only difference between the original and the clones. In Shadow the Hedgehog after 9 minutes of fighting Devil Doom Eggman tells Shadow he's the real deal but that's only because he thought Shadow needed a boost of confidence. Eggman thought, "9 minutes? Shadow should have him dead by now."
 * Or maybe he's a vampire.

Sonic is a Pirate.
We begin with the Nostalgia Critic's review of the Sonic the Hedgehog cartoon. In said review, the Critic used the "This Is Sparta" meme from the movie 300 to describe the cartoon. The movie trailer for 300 has been synched to clips from the anime series Neon Genesis Evangelion in this video. The anime Evangelion was produced by Studio Gainax. Studio Gainax also produced the anime series Gurren Lagann. Clips from the anime Gurren Lagann have been synched with the movie trailer for Pirates of the Caribbean 3 in this video. Therefore, if we logically connect all of these elements, Sonic is actually a Pirate.

Alternatively, in a more direct reference, Sonic the Hedgehog searches for golden rings. Now, the only people who actively search for and collect golden rings are pirates, treasure hunters, and archaeologists. Now, since Sonic is too young to be Indiana Jones, he must therefore be a pirate.

Dr.Robotnik(Dr.Eggman)is the real ultimate lifeform.
After Gerald constructed the ultimate lifeform, Shadow, he always had the idea something would go wrong with him being created partly from Black Doom's blood so he had the idea to create his own ultimate lifeform which was started and completed years before. He decided to let the ultimate lifeform constructed from his blood, Dr.Ivo Robotnik, live a normal life. Gerald had his son raise Dr.Robotnik as his own. Incase anything went wrong with his later project, Shadow, he would tell Eggman so he could grow up and defend the planet but never got the chance because he was executed by the government. Dr.Eggman being the ultimate lifeform is the reason for his incredible intelligence and amazing speed. Even till this day Dr.Robotnik doesn't realize what he really is and that's why he only uses his ability to run fast when he is in need of it and has a good motivation, Sonic chasing him.

Sonic sleeps with a Blaze plush
And vice versa.

The Wisps descended from the Xorda, or are related somehow.

 * Both are called alien squids by the fandom, they give powers and help bipedal, super-fast animals undergo changes in their body by giving them powers/evolving them at a very fast rate, and if you'll notice, the Nega-Mother Wisp really does resemble the aliens in the comics! Purple tentacles, massive head, you could say they're Canon Immigrants.

Dr. Robotnik is the Hero Antagonist, Sonic is the Villain Protagonist

 * Sonic is really an alien from the planet Scalisco who enslaved mankind, and Robotnik is sick of humanity being imprisoned, so he created an army of robo-animals to battle the evil Scalisconians, while they all try to stop him so Sonic can retain his control over mankind.
 * That'd make a bit of sense with the original games but what about the 3D ones where it specifically shows that Robotnik wants to take over the world and that he's hated (BY HUMANS) across the land for that reason?
 * What. The old games' whole backstories disproved the theory anyway.
 * The humans got comfortable with Sonic and friends ruling over them, Robotnik became a well intentioned extremist.
 * We have seen the government in the 3-D games, as well as who controls it, and none of them are anthros. Additionally, if Sonic were a a dictator of some sort, he'd have an army by now.
 * He does, he's got an army of furries.
 * I get the joke, but that wouldn't be enough furries to make a company, much less an army.
 * He then invented a cloning machine.

The various anthropromophic lifeforms of the series are all the same species: a large special form of Chao
The same way that it's theorized that Chaos is some sort of Uber Chao, Mobians (or whatever you want to call them) are a middle ground. That's why they don't have toes and why they wear gloves; to actually define their hands. No gloves and their hands go back to being rounded pseudopods.
 * Maybe Dr. Eggman is of this species too! He wears gloves and has Rubber Hose Limbs, like the anthros.
 * Could be! He grabbed a human the same way the chao grab little animals and absorb their traits.
 * Chaos gets "bones" when it absorbs chaos Emeralds. The Mobians get 'bones' (or some sort of vaguely ridged structure) and strength from the ambient chaos energy and the rings.
 * Perhaps Rouge absorbed Chaos Emeralds once, and that's the reasons she looks that way?
 * The chao in SA 2 gain abilities based on the chaos drives you give them. Enough of the green type, and they start to look like a mini-Sonic, and even gain some of his running ability. The red ones make them look like Knuckles, and improve their climbing ability.

Sonic the Hedgehog is the true ultimate lifeform. Shadow is/was in denial of this fact

 * While Shadow does SEEM more powerful, the fact that Sonic is able to not only keep up with him, but even occasionally beat him without the flashy moves Shadow uses. Though, he's proven to be capable of them also (something he learns out of no where). Shadow hints at this during Sonic '06 when he's unconfident that they would be able to win without Sonic.
 * Shadow does admit this in Sonic Adventure 2 (though he may have forgotten after losing his memory), but the fandom seems to be split on this.
 * Another strong piece of evidence is the "Super Sonic" prophecy from 3 & Knuckles. Note that Shadow is designed to resemble Super Sonic (at least in silhouette). It stands to reason that after the Biolizard proved... unsatisfactory, Professor Gerald turned to the ancient prophecy, attempting to create a Super Sonic that didn't require the Chaos Emeralds to access Chaos Energy.

Dr. Ivo Robotnik of Game universe is a Well-Intentioned Extremist on a path of revenge
Think about it. The agents of G.U.N. killed Ivo's innocent cousin. Robotnik's genius grandfather, who was an idol for him, was executed by the same government of the United Federation for no real reason. Their death traumatized Robotnik's mind. He was shocked by the fact that his grandpa, the one who was always working to make the life of the planet's denizens better, was so easily eliminated by the militaristic and paranoid government.

Ivo Robotnik decided to avenge the family, while his grandfather also formulated the plan of "revenge from the grave" shortly before the execution. But, unlike the latter, Ivo never wanted to destroy all life on the planet (in fact, it was hard for him to believe that Gerald, young Ivo's hero, meant to kill everyone on the planet). He just wants to prove that the U.F.'s decision was wrong, while creating a better government for all people of the planet. HIS government. Look at the screen during the declaration of Eggman's ultimatum in SA2. The screen says "Robotnik Empire". The empire of Eggman, and the empire of the whole Robotnik family, created to avenge the murder of the innocent.

And why is he well-intentioned? Well, Dr. Robotnik from the game universe is not a maniac who wants to roboticize every living thing (though, he IS an egotistical bastard, and he isn't afraid to kill anyone standing in his way). He actually wants people to live under his rule ("Those idiots! They're destroying everything! How can I take over the city and build the Eggman Empire if there is no city?!"). And with his endless resources and perfect robotic machines, Dr. Robotnik can actually build a truly utopian society. He even doesn't really want to kill Sonic and friends, those furries just always get in his way (well, in the early games and the first Advance, Robotnik actually provoked them by using their smaller, less anthro friends to power his machines).

By the way, Dr. Robotnik also has another plan. If he can't conquer the planet, he will create the Eggmanland. What is the Eggmanland? Just another giant robotic base as shown in Unleashed? Well, the base is only a part of one great complex. Why does Robotnik need all those Chaos Emeralds or Gaia's powers to create a base, or even a city? He already has (had?) the big city and the base in Scrap Brain Zone, all in the first game (where he ALSO was on a quest to create the Eggmanland as the original Japanese manual says). Eggmanland is not just a city, it is Robotnik's image of an ideal country, the robotic utopia where machines do everything for you. Of course Ivo needs unlimited energies to power this thing. If such utopia is created, while the whole world is in chaos (maybe even caused by Dr. Robotnik himself), many people will choose it as a better place to live than the Federation, thus gaining a moral victory and a victory in world domination for the Robotnik family.
 * This is a theory that this troper has considered as well, and I agree with most of your points. In addition:
 * Him not really trying to kill Sonic and Co is something I at first objected to. Well, at least, when it comes to Sonic. Remember Sonic Adventure 2? Not to mention the HUGE mech he used against Tails in Sonic Adventure. Though you did mention that the gameverse Robotnik is willing to kill people if they get in the way, and Sonic and friends are always getting in his way, so you make a good point. I don't think Eggman's robots have ever really attacked citizens, even in Sonic the Hedgehog 2006, they just intimidated them a lot.
 * At first, I couldn't understand how Eggmanland could be considered a utopia. It is really, really cool, if not extremely hard to beat, I must admit! But do you SEE those clouds over it? It's very clearly daytime since Sonic is in his normal form when they first arrive, yet it's very dark and the sky is filled with smoke. Unless it wasn't smoke and just ordinary heavy clouds that were red from the lights of the city.
 * Unfortunately, if the bad futures from Sonic CD are anything to go by, Eggman's reach exceeds his grasp, and if he ever is successful, his machines will grow beyond his control, bringing about an apocalypse, possibly even enslaving him to it.
 * We don't know why this happens. Maybe it's because of the emeralds. Maybe Bad Future-Robotnik got mad of all of his Chaotic Power. Or maybe it's just Rule of Cool. Past or Present, Good or Bad Future, Metallic Madness is still Dr. Robotnik's main base on the Little Planet. Maybe the Good Future is the actual result of Robotnik's success (as you noted, in Bad Future machines overpower his ego - even Eggmanland Logos are broken!). The Past doesn't look so bad and the Present is just a big base. If anything, Bad Future is bad for Robotnik too.
 * Except that yes, we totally what causes the bad futures. Destroying Eggman's robot teleporters creates the good future, whereas leaving them keeps the bad future, proving that yes, they're the result of Eggman's actions.

Robotnik of Sonic the Hedgehog is a businessman selling off the resources of Mobius to someone off-world
We see evidence that he spends time off-planet, and it makes more sense that he is exploiting Mobius' resources for profit rather than For the Evulz. In that context, it also makes sense that he employs mostly robots, since no human except Snively would ever work for him.
 * The off world person is.... the game Robotnik.

The Sonic X version of Amy is the reincarnation of Haruko from FLCL.
And she's only pretending to be devoted-and-sweet-yet-moody, because that's the type Sonic was most likely to become deeply attached to romantically. When the time is right, she's going to use him in order to obtain Atomsk, no matter who happens to get caught in the crossfire.
 * Does this make Sonic Haruhi?

Evreything but Robotnik, humans and twilight cage denizens included, is a robot.
They were made by the Great Beings.

Tails is a zenko kitsune from Japanese mythology
It would explain his obscene intelligence, why he has two tails, his flying ability, his strategic insight, and all the age and gender confusion (kitsune are masters of trickery in this respect). He can still be a little kid, too; he will grow more tails until nine as if he gets older.
 * Tails was indeed originally going to be a kitsune. They changed it to a fox when they realized that they would have to explain to western audiences what a kitsune is. The character was already fairly well developed before being a kitsune, as shown by the appearance in an early arcade game of "Ray the Flying Squirrel". The same game was the first appearance of Mighty, who is essentially a draft version of Sonic that was later redrawn in his current form.

Robotnik wears a disguise when he fights Sonic
Specifically, a bald cap, fat suit, and a false nose and mustache. That's why his legs seem preposterously skinny, and why his mustache is so large. This way, he's still able to go out in public when he wants without the police or GUN swarming all over him.

The Tails Doll is killing the cast.
He has slain Mighty, Bean, Bark, Nack/Fang, Ray, Eggrobo, Illumia, Void, Ali Baba, Yacker, Metal Knuckles, Proffesor Pickle, and Yacker's Mom so far, feel free to add others.
 * Metal Knuckles (who's actually named Mecha Knuckles, thank you) made a reappearance in Sonic Advance 1. I agree with the others though.
 * That's a different Mecha Knuckles, actually.
 * The Eggrobos are mass-produced, so if The Tails Doll got one, Eggman has made more since.

Maria was behind everything.
Sonic Adventure 2 and succeeding games (specifically Shadow the Hedgehog and Sonic Battle) establish much of the background for the series (Eggman's upbringing, GUN's involvement with the Chaos Emeralds, etc.), and it's all tied to two things: Project Shadow, and the death of Maria. We are not given conclusive proof that GUN killed her during their invasion of the ARK (which, we learn, was used to control and shut down Project Shadow), and she may have been among the people captured who knew about the experiment. This makes sense when you understand that she was very close to her grandfather (his experiments were part of a larger experiment to cure her NIDS) and had a special friendship with Shadow before the raid, giving her special, unique insight into the project that the government could use to restart it under their control. Since GUN had already captured or destroyed everything else relating to the project (including Shadow), it's possible that they kept her alive and around as a bargaining chip to motivate Gerald to work for them. When that failed, they set her up to be their conduit to the project's information. From there, who knows where she went in GUN's ranks? Highly improbable, to be sure, but considering the known GUN conspiracy it's based on, not far out in the range of possibility.
 * In one "possible future" in the comics, it's shown that Maria is considered a god; people pray to her statue (with wings), and "Maria have mercy" and "Maria help me" are common statements. One would think this would require more involvement than simply Shadow talking about her.
 * Wait, did this occur in the possible future where Shadow rules Mobius as an evil tyrant or the future that comes after that? Then again, considering that all those "possible futures" are supposed to be 25 YEARS after the canonical comics, it doesn't make much sense for Sonic and the gang to convert to Maria-worship that quickly.
 * For this, I simply say: Every time they show the flashback, THERE IS A GUNSHOT JUST BEFORE SHE FALLS TO THE GROUND. Sounds like concrete evidence of her death to me.
 * Sounds like evidence that she was shot, not that it was fatal.
 * Sounds like evidence that she was shot at, not that she was hit.
 * I think the point was that it's Shadow's flashbacks. Though that would mean she'd have to take an assumed identity after leaving the ARK to fool the current GUN commander. Though if she did become a higher up at GUN, it might be possible for her to fool the commander (assuming commander isn't the top position). Then again, what would her motive be? Also, we know people died because of the GUN commander. I really doubt she'd set up that complex a gambit for no apparent reason. Then again, WMG.
 * Not possible. Gerald finds her name among those who died after the Project Shadow Shutdown, which is what drove him insane and set the events of SA2 in motion. GUN also couldn't have altered Gerald's diary, since even finding it would have allowed GUN to properly disable/destroy the ARK before it turned into a Colony Drop Doomsday Device. Shadow had ruled for 5 years straight in the 25 Years Later arc, giving him plenty of time to set up Maria as a god, and given how harsh his rule, getting a symbol of hope in Maria was what the people clung to, as well as what Shadow wanted in the first place; a way to peace. Also, remember the WMD left behind in the ARK, the Eclipse Cannon? Considering all Shadow had to do was power it up to make it operational, and the Artificial Chaos experiments were still running loose by Sonic Adventure 2, this disproves the theory of GUN having captured/destroyed everything save Maria. In turn, this eliminates the chance of her being a bargaining chip for Gerald's co-operation with GUN, since Gerald did have something to motivate him in destroying the world. As such, Maria couldn't be behind everything, just short of a My Death Is Only the Beginning in helping Shadow escape the raid and telling him what she did.
 * She is the Tails Doll.
 * Ah shit, son.

Sonic and/or Robotnik are clones of Shadow and/or Gerald respectively.
And Eggman Nega is a clone of Robotnik.

Both Sonic and Robotnik/Eggman Nega have similar looks and abilities to their past counterparts - too similar to chock up to experience or even Identical Grandson-ness. Gerald's similarity to Robotnik can be explained, as he also has a granddaughter (though it's still similar enough to make one wonder...); but there is no evidence that Robotnik ever had or ever will have romantic encounters with women, and his technological skills coupled with his grandfather's newfound notes on biotechnology make him ideally suited for self-cloning. Shadow was created in a lab using alien DNA and sealed throughout Sonic's creation; therefore, their special similarities cannot be adequately explained as coincidence - especially not after Sonic is shown to use Chaos Control near the end of Sonic Adventure 2, something that Shadow can do effortlessly, something Sonic didn't even know he could do. If Sonic is a clone or recreation of Shadow and the project that created him, it explains a hell of a lot.
 * Problems:
 * 1) Gerald is short and skinny and looks nothing like Eggman.
 * 2) Every male hedgehog that has ever appeared in the Sonic game series looks like Sonic and can use Chaos emeralds.
 * Gerald still has the same general build and facial features as Robotnik. The differences in their appearance can be explained away by Gerald's extreme age - he was old enough to have grandkids, after all. The only male hedgehogs we know of are Sonic, Shadow (a clone or artificial life form), and Silver, who is from the future or an alternate reality. Of course they are all be able to use Chaos Emeralds, and of course they all look similar; if Silver's from the future, he could be the result of another attempt to revitalize Project Shadow gone wrong - very wrong, given that his powers are radically different; if he's from an alternate universe, he could be that world's version of Sonic (or Shadow).
 * Amy Rose is a hedgehog who uses the Chaos Emeralds to access Hammerspace. According to Sonic X, Amy has about the same level of super strength as Knuckles. Just less actual fighting experience. She must be a gender-flipped clone.
 * Back to the cloning thing: Maybe it's the other way around with the hedgehogs? Shadow seems "better" at Chaos Control than Sonic, who in most continuities either discovers he has the ability by chance or doesn't show as much finesse with it as Shadow. Isn't it more logical to assume Sonic is a prototype and Shadow a "newer" model?
 * Shadow's over fifty years old, whereas Sonic is, what, 16? Plus, we have no clue how long Shadow's been practicing. We see Sonic successfully use Chaos Control on his first try with a fake Emerald. That implies prodigious talent.
 * While this is true, Shadow is implied to have spent most of his fifty years in stasis.
 * An original is frequently better than its copies, especially if it isn't fully understood. Otherwise, there would never be Porting Disasters.
 * The Similarity is a Coincidence. Professor Gerald had been on the Floating Island so long that he was able to recreate the Shrine to the Master Emerald. Also on the Island is an Ancient Echidna Prophecy depicting Super Sonic and Eggman's Giant Mecha fight. Shadow was most likely based on this. Note that Shadow's Spines and Eye color are similar to Super Sonic's. Shadow is a clone of Sonic before Sonic was even born.
 * Sonic could still be Shadow's clone even then. It's a Stable Time Loop if he is, but once valid prophecies get added to the mix, stable time loops and Temporal Paradoxes become par for the course.
 * It's also possible that hedgehogs just have a genetic tendency for powerful chaos control; Shadow is an artificially enhanced version of the best template Gerald had to work with, and Sonic is a naturally occurring mutation. While Shadow was "made with [black doom's] blood", that doesn't rule out Gerald beginning with a set of chaos-enabled hedgehog genes.
 * It's also possible that Sonic was able to quickly grasp Chaos Control was because of his past experience with Chaos energy. He had never used it to warp space-time before, but he already knew how to access the energy. This is supported by his being able to intuit exactly what Shadow did during their first encounter with only the words "Chaos Control" and Shadow's apparent teleportation to work with.

Gerald based Shadow on the Angel Island ruins.
This is an inversion of the "Sonic is a Shadow Clone" theory, and a short explanation is there. Longer version: Gerald finds the murals in the Hidden Palace Zone from Sonic and Knuckles and sees the mural that's an illustration of the Doomsday Zone from that game, in which Super Sonic and one of the larger Eggbots are duking it out over the Master Emerald. Gerald concludes that the master life form for controlling Chaos Emeralds must be a flying hedgehog, makes one, and gives it rocket skates. We know Gerald was researching ancient echidnean history. The ARK is filled with Artificial Chaos (which are explicitly labeled Gerald's doing in Shadow's game); and the end of the Cannon's Core stage, and a key point in Gerald's revenge scheme, is a copy of the Master Emerald shrine from Sonic Adventure. Also, Shadow's wild spines are identical to Super Sonic's. His spinning aura is yellow instead of his dominant color; black and red were likely not his natural nor intended fur colors, but they came from his alien blood (Black Doom points out that they share the same colors).

Chao are actually Lovecraftian horrors.
Or they are Deep-One style favored minions thereof. The first Sonic Adventure provides lots of flashbacks to the fall of Angel Island, ostensibly because the final boss wanted to stop them from stealing the Chaos Emeralds. However, he doesn't become massively destructive until the Angel Islanders start punting chao out of the way to get at him. Likewise, Tikal's negotiations in the final ending can be read to mean, "Unlike the last few civilizations you have destroyed, the humans think that the chao are cute. That means they can live." Then there's the way they gather around places of world-destroying power, chanting irregularly in incomprehensible tongues.
 * 'Ostensibly because the final boss wanted to stop them from stealing the Chaos Emeralds'? The final boss destroyed Angel Island entirely because of the Chao genocide.
 * Chao appear to absorb the life force from small animals to gain some of their power.

Game Knuckles is older than we think.
The only memories he's had of his past is him, alone, on the island, guarding the Master Emerald. Now, granted, he may not have any memories of his time as a baby; but around 3-5 years old, he should have some of his parents, his family, his relatives, friends, etc... and he doesn't. Also, Sonic Adventure hints that the Echidna race was all but wiped out by Chaos after Tikal's father tried to steal the Chaos Emeralds; however little would be left most likely wasn't large enough to be a viable breeding pool. They did state, though, that the survivors became the guardians to the Master Emerald, so it's possible that they -- with their petite numbers -- were granted extended or eternal life and youth to guard the gem and the island from invaders. Thus, Knux isn't Tikal's distant descendant; he's a close friend or neighbor to her all those millennia ago.
 * If Knuckles was that old, you would think he wouldn't be so hardheaded and easy to fool. However, Knuckles has stayed on the island, guarding the Master Emerald, alone for most of his life; it makes sense that he'd be distrustful of strangers and ignorant of the world outside the island. He might even be senile.
 * The Sonic Heroes game booklet flatly lists him as 16. However, Sonic Heroes also lists Tails and Charmy as younger than what they were originally listed as.
 * Tails has always been eight in the games, as seen by Sonic Jam's character profiles. Charmy...has a combination of localization issues (he was only sixteen in the American manual, he had no age in Japan) and wild mass guessing involving his very obscure origins.
 * Ha! Echidnas, unlike most mammals, lay eggs! It's entirely possible that Knuckles was fertilized before Perfect Chaos first attacked, and his egg was put into a state of suspended animation by the Master Emerald, the cold of Ice Cap, or whatever. Because Destiny Says So, his egg was eventually incubated and hatched sixteen years before the events of Sonic Heroes. Of course, this doesn't solve the problem of who taught him to speak, among other things.
 * Remember, in Sonic Adventure, Tikal can telepathically be a talking glowing ball of light wherever she wants to. She raised him.
 * In the comic books, he is said to be a lot older.
 * Which comics are these? The USA's "Archie" series has it that Knuckles is the latest of a family line of Guardians, and there's an entire civilisation of Echidnas in hiding on the island- Knuckles was basically kicked out at a young age and forget they existed. The UK's "Fleetway" series established Knuckles as being from the Echidna Empire, a guard who was placed in cryogenic stasis and awoken centuries later, after his race had been destroyed, and with selective amnesia so he didn't know how he'd come to be in this state.

Eggman has cybernetic limbs.
Despite being quite rotund, his legs are ridiculously thin; they shouldn't even support his massive girth, let alone extend from it. He has often shown the ability to outrun Sonic on foot even though Sonic is supposed to be "the fastest thing alive". Both of these can be explained easily if you assume that Eggman's legs are advanced (nonliving) bionics.
 * 90% of the characters' bodies defy biological explanation anyway... Sonic's head is huge, Knuckles has dreadlocks, and Tails can fly with his tails. (Cream can fly with her ears, too).
 * You think Sonic's head size is the biggest problem? What about the fact that he can run over 700 mph when his legs are as thick as AA batteries? I'd say that's probably more biologically impossible than his large head.
 * Maybe they're all robots. That's it! That's the explanation! Everyone's already been roboticized; they just don't know it yet.
 * No, no, they were all robots all along, created by Eggman. It's all part of a test by him to prove that robots are a superior form of existence. He'll keep on pushing them until he dies and world peace is achieved.
 * Seriously speaking, Eggman has resurrected himself time and time again with cybernetics, leaving him barely human at all. This is totally the way to go.
 * Maybe he's trying to make a good enough robot for one of Wily's contests?
 * Wily held that contest exactly once, with the express purpose of stealing the eight finalists.

Eggman is a Sumo Wrestler.
Self-explanatory.

Chris hallucinated the entire Metarex Saga in Sonic X.
...What? It definitely plays out like the kind of thing an 18-year-old science-freak would think up, particularly if he had extremely dramatic and nearly absent parents and a genius grandfather, and had spent a portion of his childhood racing around after a blue hedgehog. It's possible that he dreamed the whole thing, right down to the pretty, semi-distressed damsel.
 * Chris is probably open-minded enough not to expect a damsel straight out of a comic book -and he says in canon that Cosmo reminds him of himself when he was younger. It's natural that he wouldn't want her to be entirely useless; hence, she ends up saving the universe, albeit dying in the process... He shouldn't have wanted the dying, but if this IS a hallucination, then it's possible. Alternatively...
 * This would explain the Character Derailment Tails went through.
 * How was he character derailed? Asides from suddenly no longer going 'eww' around girls and suddenly having to captain a ship on a quest to save the galaxy (which I guess should probably mess with a guy a bit), he seemed pretty much the same to me.

Chris never actually made it to wherever Sonic X is set (Some people refer to it as Mobius).

 * It's not one hundred percent certain that Chris's "real" body arrived in Sonic's world when he pulled the Transportation-Without-Chaos-Energy thing. By rights, transporting between worlds without chaos energy should not be possible, so how did he even manage it? A possible explanation is that he didn't. The boy that appears in Sonic's world is a projection of his actual self as the Master Emerald remembers him; hence, he comes through the portal eighteen and ends up looking twelve, and with all his mental and cognitivre faculties in place. His mind is possibly there, but the real Chris's body is contained within the Emerald itself on some level in the same way as Tikal... This leads to some rather disturbing theories about what happened to him when the Master Emerald exploded.
 * Yeah... I remember Tails once saying something quite like this in the brazilian dub, only he said the emerald kept Chris's age instead of his self. It's not farfetched to think he was a little mistaken about just WHAT was kept there, he's just a kid and that's an ancient device of power, after all.

Shadow, Sonic, and Silver are all aspects of the Ultimate Life Form Research Project's final goal.
By the time the space station ARK was completed, technology had already found a reliable and efficient way to produce energy from "crystals" of all types; this technology had become mature enough for operations in space before hitting a bottleneck. While crystal energy was stable, there wasn't nearly enough energy density for truly impressive operations. The only more effective energy sources around were the Chaos Emeralds, but no practical means of getting real energy from them were available. The only known method to access the Chaos Emerald energy involved living beings, and only a few living beings were capable of doing much of anything with them (the Echidnas).

~70 years before the events of Sonic Adventure 2, a major research project toward developing a biological being capable of harnessing the full energy of the Emeralds for research toward conventional mechanical systems was developed; the result would be immortal and incredibly powerful and thus called the Ultimate Life Form. While the original test subject, the Biolizard, was capable of accessing a previously unknown level of Chaos Emerald energy, it still didn't pull the full amount from a single emerald. This was enough to bootstrap advances in conventional crystal energy research, and begin (hugely inefficient) methods of pulling energy from the Chaos Emeralds for power generation. This method replaced the ARK's original reactor core, which had previously taken up a sizable portion of the station.

Hoping for future successes on these lines, the scientists began work on the next phase of the project, the being known as Shadow the Hedgehog, the original Hedgehog. This creature was capable of using Chaos Emeralds to generate vast energy fields and freeze time. Super Forms are theorized, but never tested (since removing every Emerald from the reactor core would also shut down some life support). Shadow is used to leapfrog future research, build a basic. Unfortunately, Shadow is also virtually impossible to create from existing technology; a deal is brokered with Black Doom in return for the underlying biotech and blood samples, with the Humans planning to double-cross Black Doom with the resulting data. Even worse, the Eclipse Cannon is nearly discovered by Black Doom, leading Planet Gov to "shut down" the "traitorous" project leaders. Maria is accidentally killed in the event, but manages to put Shadow in an escape pod first rather than letting him be destroyed. The ARK is decommissioned and all Chaos Emeralds brought to the Planet in order to appease Black Doom, while final upgrades to the Eclipse Cannon -- and the newly genocidal Dr. Gerald Robotnik's doomsday device -- are quietly put into place.

On the ground, new research projects continue in order to further prove Chaos Emerald Tech. At least one of these generates a new template based on Shadow but without the Black Doom blood sample, and at least one other copy of this template is made with some modifications. It's not clear whether Sonic, Silver, or some other hedgehog is the third generation, and which is the fourth generation, or even if the fourth generation's modifications assist in Chaos Control or even actively harm it. One of these projects, Sonic, escapes during an early experiment with at least one Chaos Emerald, but does not activate Chaos Control methods with it. This * may* be as recently as 16 years ago, but the effective immortality of all Chaos Hedgehogs makes the point moot. Silver (and possibly other Chaos Hedgehogs) are created, but left in stasis. All of them, Silver and Sonic included, have basic understandings of modern science's knowledge about Chaos Emeralds embedded into their brains, but the process is inefficient and only activates in certain conditions.
 * Whichever one actually is the Ultimate, however, is still up for grabs.

The reason Shadow is so forgetful...
...is because Gerald purposefully designed him that way. Shadow’s going to live a long time, and possibly go through some more trauma-inducing events. Gerald strengthened his tendency to suppress memories so he’d be less likely to go into Heroic BSOD at critical moments. Only Gerald couldn’t complete it before the ARK incident, which is why it never works out how it should.
 * Or, perhaps because Gerald Robotnik probably designed Shadow to be immortal, there is a method to "reboot" his memory to avoid the "time dillation" problem normally associated with immortality.

Sonic's powers include an immunity to nausea, dizziness and G-forces.
Most speedsters would have this, but Sonic is arguably the most acrobatic and fun to watch super-speeder of them all, and can jump all over the place and take crazy falls without a sweat (or even taking damage). Thus, I theorise that Sonic would make a great fighter pilot. Like most of Sonic's abilities, this bled over to other characters in games like Sonic Heroes. Shadow and that other guy seem to display this same ability.
 * Does anybody else want to see this combined with the above speculation about fast mental processes, and see what Sonic would be capable of in the Shinkirou? (I mean, look at the combat... The pilots have got to be constantly on some improved variety of dramamine.)

Sonic uses the Speed Force for his running.
According to Flash Rebirth, the Speed Force exists in every time period,place and dimension simulatenously. This include the Sonic The Hedgehog universe. How Sonic tapped into it is unknown, though it's likely due to harnessing Chaos Energy. Perhaps, before the games started, he discovered a Chaos Emerald. The reason why Eggman is able to outrun him is because he's had far more experience with the stuff.

Sonic, Shadow, and Silver are all clones of the original Shadow.
Professor Gerald was working to create the Ultimate Lifeform, however, GUN wished to use Shadow as the perfect soldier. Gerald refused, and GUN stormed the complex. Knowing that Shadow would never cooperate with them after killing Maria, they eventually created three clones of Shadow: Silver Hedgehog, with all of his dominant soldier genes, Sonic Hedgehog, with all of his recessive, flawed soldier genes, and Shadow Hedgehog, with the perfect blend of both.

Shadow Hedgehog was the first to be created, however, he still retained the memories of the original Shadow, and had to be put into suspended animation. Silver was used to test nanomachines that gave the user psychic powers, but was deemed too dangerous, and also put in suspended animation, eventually waking up in the future.

The last remaining clone, Sonic Hedgehog, was sent to defeat Dr. Eggman, who threatened GUN's control of the world. Unbeknownst to them, however, Eggman had retrieved the body of the original Shadow, and used it to create Metal Sonic.

The rest is history.
 * Someone has been playing too much Metal Gear Solid.

Sonic gains his super-speed from a severe case of Ingrown Coffee Pot
Common in hedgehogs, they say?

Amy uses Functional Magic to summon her Piko Piko Hammer
In her first appearance, Amy dabbled in magic and uses Tarot cards to predict when she'd meet her true love (and ran into Sonic on the way, a good enough excuse to become his Clingy Jealous Girl). Whether that was accurate is up for debate, but her other limited dabblings in magic gave her access to a magic hammer (or as seen in Sonic X, an unlimited supply of hammers). This may or may not be related to Thor. She could have been a wizard if she wanted to be, but ended up going barbarian instead. (She's the king of Unstoppable Rage after all)
 * This is slightly justified both in comic appearances (where the tarot fascination stuck) and in Sonic Chronicles, where she's once again using Tarot cards, this time to curse enemies. Also, since when has such a kid-friendly looking hammer caused so much death and destruction? Clearly it isn't simply a giant squeaky toy hammer.
 * This could also be the reason for her invisibility powers in Sonic '06.
 * Amy uses Hammerspace to summon her hammer. Not sure about the Tarot cards though.

Tikal is a hydrokinetic; Chaos is simply her 'focus'
It's shown repeatedly that Tikal "talks" to the water in various flashbacks in Sonic Adventure, but aside from one scene at in the ending sequence of the game, Tikal and Chaos are never seen at the same time, and even then only once shown in the same shot. The Reveal in earlier flashbacks of Chaos starting to form could just as easily be the echidna's water-controlling powers coming to bear fruit, and it's easily justifiable that Chaos attacked the ancient race of echidna not out of rage, but because he was simply a construct of Tikal's, used to keep the chaos emeralds, and in turn the chao that came to live in that habitat, safe. In addition, if Knuckles is any indication of the typical echidna gullability level, it's safe to assume that Eggman conned Tikal into summoning forth Chaos once more, much like he had earlier conned Knuckles into protecting the emeralds for him to steal.
 * So would this mean that she's losing control of Chaos when her emotions get the better of her? It's been a while since I played the games, but I remember it being pretty clear overall that she's struggling to bring him to a more manageable, less homicidal state - something that shouldn't be a big problem for a person who can out-and-out control the water.
 * Perhaps it's all a facade of Stepford Smiler levels; she may not be losing control of Chaos himself so much as her own emotions - the struggles to calm him being in fact the struggle to conquer her own thinly-veiled rage and frustration.
 * There's always Tikhaos http://archiesonic.wikia.com/wiki/Tikhaos

Sonic and co. are all Ridiculously-Human Robots.
Or in this case, ridiculously animal-like robots. Think about it! Why doesn't Eggman just nuke Sonic already? Why do they never seem to age? Why are their ages being constantly retconned? Why are they immune to things like G-Force, like the above entry states? It all makes sense if one considers them as non-organic beings.
 * Would explain a lot. To go father: If they are EGGMAN'S Robots, who rebelled, than we would have.... Something that sounds like Crash Bandicot.
 * But explain Bunnie Rabbot, then.
 * She was partially skinned.
 * Here's the story: The Tails Doll wiped out all humans except Ivo Robotnik. Robotnik made replicas of humankind for his own pleasure. He got bored, so he made a nemesis. Then for a race, the Tails Doll came back to try and make Robotnik lonely again.

Amy Rose is a robot.
Robotnik designed Amy Rose as the perfect form of surveillance. He programmed her to stalk Sonic at all costs, and so keeps tabs on what he's doing to allow him to plan his schemes. This also explains just how the hell Amy finds the guy all the time: she's got LITERAL radar or something along those lines for the guy. It could also explain how she does stuff like make her hammer disappear- it's all just her awesome Robot Powers, or something.
 * This would also explain why she gets captured so often-she's secretly going willingly with Eggman during these "captures". Eggman is having her get close enough to Sonic and friends so that Eggman could use her as a faux bargaining chip against them whenever he wants!
 * Sonic will eventually find this out in the future and will either end up killing her in a battle, or will purposefully allow her to kill him.

The three main characters from the cartoon Sonic Underground are each representing a main character from the games continuity
The Sonic-sibling group in Sonic Underground are the counterparts of Sonic, Amy and Tails from the games, made realated.
 * Sonic is, of course, Sonic(no need to explain. He's just a bit more childish)
 * Sonja is Amy. They're both pink, stereotypical girls, obsessed with romance and there are many things on the show as well, that makes you wish that Sonja was NOT Sonic's sister, just to avoid incest. Their personalities are very simmilar in general.
 * Manic is Tails. The great differences between Manic and Tails personalities steem from the fact that Manic was raised by thiefs. His mother originally intended to give him to someone else, but the thief "adopted" him "accidently". Essentially, Manic is what Tails would be, if his upbringing and background where different, except a hedgehog. However, the two still share simmilarities, like great mechanic skills, a BFF relationshp with Sonic and sometimes distrust in their own abilities.

Robotnik and Eggman are split personalities.
The two seem so different that this is the only explanation. "Robotnik", the dominant personality, is more military-minded and focused on his goal, with less humanity to him and aware that he is genuinely terrifying and using it ("What colour is my heart, Snivelly?") "Eggman" is more childlike, showing such traits as narcissism (expressed through the Egg Pawns), a fondness for games and "fair play" (Eggmanland, anyone?) and a habit of boasting. Both share similar traits - obsessed with world domination, ruthlessness (Eggmman's theme reveals he progams his robots to have no self-preservation, despite the fact Sonic minces through them easily), and blessed with innate mechanical genuis, although Robotnik's style is wildlife inspired whilst Eggman's is more anthropomorphic.

So how did the switch happen? Perhaps Robotnik suffered brain damage before the start of Sonic Adventure and Eggman moved in. Perhaps Eggman has come out as his threat level has declined. Or perhaps the two switch freely, but we never see the other side depending on the game. Eggman, however, is clearly here to stay.


 * Snively? Terrifying? You're confusing continuties. Canonical Game Robotnik has always been relatively the same. In fact, Game's Dr. Ivo Robotnik has "Eggman" as his villainous side, while "Robotnik" is what he was before he became the villain and started to fight with Sonic.
 * Besides, Robotnik was pretty evil in both Sonic Adventures. Destroying cities, summoning gods, and blowing the moon is not really a "fair play". Not to mention hostage situation.
 * Another possibility is that the Robotnik/Eggman relationship is like the Jekyll/Hyde relationship. Eggman is the kind yet childish Emperor Scientist, who's motives can be appreciated.Robotnik is the cantakerous dictator who only wants complete power. The Archie and Sonic Sat AM Robotniks are complete monsters because they lack the Eggman personality.
 * Sa TAM's Julian Robotnik and Archie's original Robotnik, despite sharing the same design, are very different. Sa TAM's was always dark and gloomy (his relationship with Cluck doesn't count!), while Archie's was a mix of Sa TAM's and Adventures of Sonic the Hedgehog's, being a sadisctic, yet Laughably Evil Card-Carrying Villain. He even worked with Sonic on occasions. Archie's new Robotnik, "The Eggman", is far worse. Aside from destruction he brought on Mobius Prime (including genocide), in his own zone he nuked Mobotropolis and actually killed Sonic and all of Freedom Fighters... So, in the end it doesn't matters whether the character is frequently called "Eggman" or "Robotnik", both versions can be either monsters or motivated conquerors.

All the sentient animals belong to a single race not natural in origin.
Every sentient animal in Sonicworld has the same basic humanoid shape with a few cosmetic changes thrown in. It's almost as if they were engineered from a single template to have animal features.
 * They might be related to Chao. They simply grow larger and gain more animal-like features than Chao do. There might have been normal animals out there and the Mobians copied their appearance. From that point on, Mobians looked like animals and baby Mobians just copied the animal features from their parents.
 * A lot of charecters from Adventures of Sonic the Hedgehog do not fit the mold.
 * Whilst I'd definatly agree that the Sonic characters are definatly a case of Call a Smeerp a Rabbit. I wouldn't think they are the same species, let alone the same race.
 * In the comics, there are several instances of "interspecies" romance producing viable offspring. The different "species" being different phenotypes of s single species makes this a whole lot more plausible.
 * The comics function on a different planet and different logic to the games.

Shadow, Sonic and Silver are father, son and grandson
First of all, Shadow is about 50 years old, which makes him perfectly able to be Sonic's Father. Shadow, being the solitary character he is, abandoned his son for whatever reason when Sonic was young, which is why the two don't reckognise each other (aren't hedgehogs colour-blind?). And Silver, being in the future, could easily be Sonic's son, and it's possible that Sonic was killed by Iblis during the alternate future. This explains why Sonic continually tries to befriend Shadow and why all three are capable of Chaos Control. It even explains why Amy keeps getting the three confused, they just look so alike!
 * If Shadow is Sonic's dad, would that mean Sonic's mom is Maria, and Sonic and Eggman really ARE related after all?
 * Even by video game character standards, Maria died a bit young to be a mom.
 * No, Tikal is his mom.
 * ... Tikal died/ascended centuries before Shadow was created. Also, wouldn't Black Doom's genes have then passed to Sonic, rendering him immune to the Black Arms gas?
 * Maybe Tikal's echidna genes overrid the Black Arms ones completley.
 * Then why is Knuckles, who's origin may be that his egg did not hatch for centuries, not be immune to them?
 * Uhh, Tikal's genes overrid the immunity, not created it.
 * That only raises more questions. How the hell did a fourteen-year-old girl successfully become a mother? The anthros are implied to mature at the same rate as humans, and nothing regarding the echidna society suggests that ephebophilia was acceptable.
 * The other Echidnas were dead. She was a rebel. Go figure.
 * She died five minutes later than the rest.
 * And the whole time we're ignoring that Silver is 201 years younger than Sonic. Excellent.

Antoine D'Coolette is the descendent of Sparkster
Royal knight, Rocket knight. Antoine's a trained air pilot, Sparkster can fly for short bursts (and indefinitely on the shoot-em-up stages). Antoine's a coyote as opposed to an opossum, but since he and Bunny Rabbot are married in the Archie timeline mixed-race isn't a problem. Sparkster even had his own series of comics in the Fleetway Sonic series. Compare also the character design of (Archie) Antoine and Sparkster - they're just vaguely similar enough to be connected. In fact the only real obstacle for this connection is licensing, given that Konami holds the rights to the Rocket Knight.

Sonic, Chaos, and Black Doom are the same species
And that species is Chao. Chaos resembles very strongly a neutral immortal or 'chaos' chao, and Black Doom resembles a dark immortal or 'devil' chao. Here's the theory: Any chao that reaches the immortal state continues to live and grow for millenia, eventually reaching massive levels of size and power such as Perfect Chaos and Black Doom's giant form. Using chaos emeralds temporarily boosts them up a certain number of life stages worth of size and power depending on how many emeralds they use. It follows then that Shadow is a hedgehog/chao hybrid, being created partially from Black Doom's DNA. It also follows that Sonic is also a hedgehog/chao hybrid or perhaps pure chao, and his coloration indicates that his chao half comes from Chaos, or a neutral immortal like him.

The Blaze from the future and the Blaze from an alternate dimension are the same Blaze
After the events of Sonic Rush, Blaze made a wrong turn on the way to her dimension, and somehow ended up in the future due to a rift in space-time and got Laser-Guided Amnesia (hey, space and time are related, right? No one knows how on earth that spacial rift works). After making friends with Silver, she traveled back in time for the events of the 2006 game. After sealing Iblis in her, she uses Iblis' energy to travel back to her dimension and either gets her memory back or learns about everything that happened from someone else, and the events of Sonic Rush Adventure happen. Since Iblis doesn't exist, the future changed. Blaze and Silver never met each other. Silver traveled to the past using a known time-traveling method, while Blaze used a method that opened a portal not to an alternate dimension, but to the past, but since she didn't know she thougt it was so. With the future so changed, unless Blaze and Silver meet each other and travel by the other's method they may never figure it out by themselves.
 * Another alternative: the Alternate Dimension IS the future
 * Another theory -- Blaze likes to visit Sonic often, and the future isn't that far off, so the future Blaze is merely an OLDER version of herself from Sol. She makes regular visits to Mobieus well into the future. Now Silvers origin....

The werhog transformation is caused by Hordika Venom
Sonic has part of Lihikan's life force, so he can be affected by transformers and bionicle diseases.

Black Doom did not have a hand in Project Shadow
OK. Black Doom is clearly telepathic, and can see into all of Shadow's memories, even those buried by amnesia. All those "revelations" about his relation to Shadow was simply him doing what he had been doing for the entirety of Shadow the Hedgehog, scanning Shadow's mind and using what he finds to figure out just what he needs to say to manipulate Shadow. Paralyzing Shadow had nothing to do with sharing blood, it was just mind control, psychic powers at work. Now, Black Doom did arrive on the ARK, but what the future GUN commander really saw was Black Doom and Professor Gerald discussing the Shadow Project. The arrival of a sentient (albeit warlike) alien race was definitely interesting for Gerald, but I don't think he would trust Black Doom to finish his own ultimate project. Black Doom decided to hold off his invasion another 50 years so that he could make use of the "Ultimate Life Form" when it was complete. He also probably picked Gerald's mind for info about the Chaos Emeralds and Chaos Control while he was at it. Either that or he gave Gerald the idea for utilizing Chaos Control. Or a combination of the two.
 * Explain how Shadow wasn't paralyzed by the Black Leeches or whatever things at the end if he didn't have Black Arms blood.
 * Because Doom didn't want him to be! It was all part of the act, like convincing everyone he actually had a menacing body when in reality he was just a floating eye.
 * Also,Shadow is supposed to be the Ultimate Lifeform.That means he can't be killed or permanently weakened by toxins. It was part of the whole "find a cure for NI Ds" thing.

Sonic, the rest of the furries and the Chaos Emeralds were originally from Blaze's universe

 * An experiment involving the Chaos Emeralds caused a massive distortion which grabbed the characters and emeralds and whisked them away to the human universe. The residual effects of this distortion are what causes the merging of universes in Sonic Rush and any other game Blaze appears in. This is why all of them except Vanilla are kids. Vanilla could be a random bystander. Alternatively, the experiment could have been done using the Emeralds and the kids which resulted in their various abilities with Vanilla being the kids' supervisor.

Sonic and pals have a Space 'Swim Bladder'.
Think about it: how else would they be able to survive in the vacuum of space? Due to their different biology, each has an organ in their body, similar to a swim bladder (yes incorrect, I know, but it's just for lack of a better term), which regulates their Atmospheric pressure so it's at a constant level, and acts as a 'third lung' in times of emergency when there is little or no air. However, it's ability as an 'extra lung' can only function for so long - hence drowning underwater.
 * Correct me if I'm mistaken, but I can't recall any instance of space survival that wasn't upon a space station (even if it seemed like open space), or in Super form.
 * The only ones I can think of are in the Genesis endings in which Sonic/Tails/Knuckles falls to the planet from the exploding death egg. They're not always in super form.

Unleashed was not the first game Light Gaia and Dark Gaia appeared in
Specifically, I mean that they are the exact same enteties that Soul Blazer, Illusion of Gaia and Terranigma revolve around. A long cycle of the world being destroyed and reborn, repeated time and again since the dawn of time. This also means that Sonic might be the latest reincarnation of Blazer, which would explain the vague prophecies surrounding him.

Shadow and Silver are actually evil clones of Sonic
Eggman knew that Sonic will always win when he has Tails and Knuckles with him, so he needed a way to get Sonic alone. The original Sonic Power Trio is Sonic, Tails, and Knuckles. Shadow and Silver were designed to replace Tails and Knuckles, so that they would both betray Sonic and destroy him.
 * Silver was also meant to steal Blaze from Sonic and kill her, driving Sonic to suicide.

Amy is short sighted and needs glasses
How many people has she glomped thinking they were Sonic? Shadow, Silver, Werehog Sonic... She only notices after the glomp. Obviously she doesn't wan't to wear glasses as it would mess up her look. And have you tried to get contact lenses for eyes that big?

Amy is the furry version of Haruhi Suzumiya.
Not only is she a complete Game Breaker in Sonic Adventure 2's multiplayer, but her team also has an easier time taking down the Egg Emperor in Sonic Heroes than any other team. Clearly, Amy has some kind of hidden power to bend the fabric of the universe to her liking without even knowing it.
 * Evidence against- she has yet to get Sonic.
 * Sonic is her Kyon.

Eggman is the perfect human
Robotnik is able to outrun Sonic the Hedgehog with enough effort, and has shown he is also stronger than he appears, and in Sonic X manages to dodge gunfire with ease and is even able to take out a laser turret in one solid punch. Add in his exceedingly high IQ, and talk of him being possibly the most attractive fat man in existance, and you've got the ultimate human being. He also never seems to age despite the large time lapses inbetween games. Behind Egghead's blubbery exterior lies what humanity has dreamed of achieving for many years.

Sonic is Aladdin in Sonic and The Secret Rings.
The other Sonic characters are Arabian Nights characters in the game (Tails is Ali Baba, Eggman is King Shahryar, Knuckles is Sinbad) and numerous references are made to the story of Aladdin and the Magic Lamp, but Aladdin himself doesn't show up, as a Sonic character or otherwise. Why? Because Sonic HIMSELF is Aladdin. Evidence:
 * Sonic commands a Genie of the Ring (Shahra) throughout the game.
 * In the ending, Sonic takes Erazor Djinn's magic lamp, and uses it to make three wishes. Erazor Djinn is said to be the genie from the story of Aladdin. See the connection?
 * In the very last scene (after the credits after beating the FINAL final boss) we see the front page of a book with the title "Aladdin and the Magic Lamp". As we watch, the title fades out, to be replaced with "Sonic and the Secret Rings". This essentially implies that Sonic has somehow changed Aladdin's story into his own, and essentially replaced Aladdin as the main character - so Sonic effectively has become Aladdin.

One or more of the characters is a Time Lord.

 * Because who looks at a hedgehog and thinks, 'Ooh, this could be a little more Sonic'?
 * Alternate theory- Eggman is the first timelord. He invents a time machine, plays around with the time space continuum, discovers the secrets to the universe, and then clones himself to create the ultimate eggman empire. Why do the clones all look different? They regenerate on birth. Why do they have different biology? Well, does Eggman look entirely human to you? How does regeneration work? I'll tell you how, Chaos shards.

Dark Gaia is what Eggman's always been really after.
Out of everything Eggman's tried to take control of, Dark Gaia has been by far the most powerful and the most effective. He's always known about the link between the Chaos emeralds and a vast, cosmic force. All these times he's taken the Chaos Emeralds, he's been scouring legends for their true power source. In the past, he's stumbled on lesser Chaos entities and been satisfied with them enough to try his luck or simply decided that the Emeralds themselves were good enough in a pinch.

Prior to Unleashed, he hit a breakthrough: he discovered the true source of Chaos Energy was held within the planet itself! Which lead to his plan in Sonic Unleashed and our next point...
 * This may explain why Sonic Colors had nothing to do with the Chaos Emeralds: he's failed to harness Chaos Energy, and must resort alternative power sources.

Maria didn't feel the gunshot when she died.
We're given two different gunshots - in the corridor (in Shadow) and in the escape pod bay (in Adventure Two). But we don't see where she's shot. Solution to this? She gets shot in the corridor in a non-vital area, keeps running (and Shadow's not panicking because he doesn't understand that she's bleeding to death) and then gets shot as she sends him away to Earth. The problem that arises is how a human can do this, which then brings me to the disease she suffered from - a form of AIDS known as NIDS (Neuro-Immune Deficiency Syndrome). Neuro-Immune Deficiency? She can't feel pain (a condition called congenital analgia) and so kept on going.
 * It doesn't even have to be down to her medical condition. It's actually quite common for people to continue operating for a good couple of minutes before realising they've been shot.
 * I also personally put the two different backstories down to continuity errors in Shadow's head. I can't speak for the games, but in Sonic X we tend to see her memories either in a) normal full colour, or b) sepia toned, and the sepia toned images tend to be far more blunt, dramatic and/or symbolic. I would suggest that this is because (somehow) Shadows memories have been manipulated, so there are two versions. His "real" memories are in full colour, and his fake memories in sepia (maybe it was Ivo that did that so as to make sure Shadow would be angered enough to carry out his plan of world destruction - but he didn't factor in his grandaughter's influence). In Shadow's final Heel Face Turn in Maria's Request, where the dying Maria tells him how he was created to help people, the colour seems to change just a little again -there's a lot of softer, dramatic lighting going on, as if this sequence is the only one Shadow can really count on to be true, regardless of which of his other memories are genuine. I don't know if they use that colour effect in the games but it WOULD explain the different sets of memories.

Eggman is to humans what Sonic is to hedgehogs.
Makes sense huh?
 * What, fat, meglomaniacal and trying to take over the world?
 * Nah, it explains why he is able to constantly survive. on a note, he's bigger than regular humans too. (if you've beaten Sonic CD, there's a part where eggman outruns sonic. (it's an explanation for a WMG above)

Amy is Psychically bound to Sonic
Okay, think about it. if Shadow is built around an ancient Super Sonic, then wouldn't that mean that his biochemical make up is similar to Sonic's? it makes sense too, because how else would she have been able to tell that the Were Hog was sonic? i mean, he doesn't even look like him in the slightest. you'd have to be blind. To put the point simply, Amy is locked onto Sonic, as the worst possible stalker ever.
 * Uhh... Amy didn't recognise Sonic as the Werehog until he went out of his way to save her. Before that, she did her regular short-sightedness act, and then apologises and walks off, leaving Sonic somewhat annoyed and depressed that of all people, even she could mistake him for somebody else. (And that first bit probably came off a different WMG. Check first before you post!)
 * That's the thing. if you accept the idea that Shadow was based off of super sonic (which is canon BTW) you realize that everyone amy's gone after is like Sonic somehow. The werehog IS Sonic. And Shadow, even if you were color blind you could still tell him apart from Sonic. Amy also has Psychic powers. If i'm not making sense, could someone clarify? (as for the WMG above, i was just speculating on why super sonic looks so different from sonic. i have removed it, sorry!)

Sonic loves Amy back, but feels he can't be with her because of Eggman (and everyone who eventually steals the spotlight from that scientist).

 * "Fanwork" aside, Sonic never seems to be particularly annoyed to see Amy; to This Troper, he seems more frightened than anything. Why would he be frightened to see the girl of his dreams? He sees what could happen if he were to admit his feelings and they were to become a couple. He puts on such a facade, there's a chance even Tails doesn't know. It's a tragedy, really; one person (by which I mean "sentient being") knowing he could sweep her off her feet at any given moment, but is so afraid of one dying on the other that he never does. Isn't it sad?
 * Huh. It always seemed more obvious to This Troper that he was simply aware of how a fifteen year old having romantic feelings for a 12 year old girl is so many kinds of awkward by itself. A simpler explanation is that he's just going to wait a few years for her to mature more before taking the relationship to a more serious level.

That white part on Sonic's face is NOT part of his eyes

 * It's just white fur around his eyes. This was inspired by looking at this picture mentioned on the YKTTW board and noticing that his face without the blue "eyebrows" hanging down looked a bit like the white part was a mask and the black parts were his eyes. I also thought that Piplup from Pokemon has a similar kind of face, although it's more obvious that the white part on Piplup's face isn't part of its eyeball(s). Either that or that picture is correct, and animals in the Sonic world have two pupils and one big eye that is blocked by what LOOKS like eyebrows to make their faces more expressive.
 * What is ironic is that cyclopia is usually caused by a lack of the protein sonic hedgehog...
 * Ironic or Fridge Brilliance?
 * How can the white part of his eyes be fur if it's clearly textured as glassy sclera in most renders these days?
 * Furthermore, the irises move across the white area, which can only be possible if the white area is the sclera of his eyeballs.

Eggman was counting on Sonic restoring the continents in Unleashed.

 * Look what happens at the very end of Unleashed when Dark Gaia goes One-Winged Angel and floods the world with darkness. Eggman's private island paradise is unaffected, as its the only chunk of the world that's still floating halfway into space. Having finally learned that Evil Is Not a Toy, Eggman expected Dark Gaia to disobey him and go nuts, and only needed to make sure that his Eggmanland was the last area of the world still disconnected before it happened, hence why the robot mooks in Eggmanland take a heck of a lot more punishment to die than anything faced earlier in the game - it's only then that Eggman stops holding back. Not to mention the level itself being harder than anything ever seen before in the series.

Rotor and Cobar's torture/death in "Mobius: X Years Later" was a result of Bury Your Gays.
Think about it: Ken Penders wrote the first (unaltered timeline) part of the story arc. Word of Gay from him states he planted several hints that Rotor and Cobar were gay lovers. He was dropped and his replacement, Ian Flynn, took over, writing the second (altered) part of the arc. One of the first things to happen in the second part of the arc was Rotor and Cobar being tortured, with Cobar dying from his injuries. Clearly, Ian knew what Ken was planning, hated it, and snuffed it out in the cruelest way possible to spite Ken. In return, though, Ken got his revenge; said Word of Gay wasn't revealed until after Ian finished up the story arc, preventing Ian from contradicting his vision of Rotor, any longer.

The dark energy that caused Sonic's Werehog Transformation is the same energy that caused an unknown Chao to become Chaos 0
How did Chaos 0 primarily attack you? Stretchy arms. How did the Werehog primarily attack? Stretchy arms. Not to mention that a lot of the enemies from the night stages resemble Chaos 0. The part with water and Chaos Emeralds is simply exclusive to Chao. So now in the story, Chaos 0 is probably just an average Chao again.

Mighty hasn't appeared for so long because he heard the true name of a demon.
As Digger explains, armadillos are the only non-demons that can hear the true names of demons. Mighty heard one and has been curled into a little ball since.

Cheese was at one point exposed to a Chaos Emerald
Most Chao Garden chao in Sonic Adventure 1 and 2 are fairly slow, weak creatures that can only fly for a limited amount of time. Cheese, however, appears to be able to fly indefinitely, keep up with the fast-running cream, and destroy robots simply by flying into them. This would make cheese practically a superhero among chao. Now, chao are capable of absorbing both small animals and the energy sources of GUN robots. The obvious conclusion is that Cheese gained his ludicrous stats by absorbing the energy of one of the most powerful MacGuffins in the Sonic universe: A Chaos Emerald. Obviously, Cheese must be kept from absorbing any more of them, lest he become the next Chaos.

Fox McCloud is Tails' illegitimate father.
Just think about it, it makes total sense. Both are foxes, both are pilots. Fox McCloud may have just stopped off on Mobius/Sonic's Earth one day and ended up having a one night stand with Tails' mother. Fox left, Tails' mother had Tails and raised him for his first couple years, before Dr. Robotnik roboticized her, effectively making him an orphan, and Sonic found him.

Gerald is Jamie Hyneman and Eggman is a clone of him and Theodore Roosevelt.
Eventually, Jamie's show and mythbusting abilities gave him enough fame and fortune to achieve his ultimate goal: build a space station in his image and bust myths, study dead races, and create powerfull beings. He ultimately got interested in the echidna civilization, and met Black Doom while working on the ultimate lifeform project. At some point in time, he decide that the best way to continue his work after he died was to make a clone of himself. He also added Roosevelt's DNA to make it stronger. Unfortunately, somebody (possibly Black Doom) corrupted the DNA, mutating Jamie's genius into Mad Scientism, and Roosevelt's love of the hunt into a desire to kill and/or roboticize all non-humans.

Sonic is Shadow's prototype, made using Chaos' data instead of Black Doom's
Think about it: Shadow is black/red and has chaos powers because he has Black Doom's data. Sonic looks similar to Shadow, is blue, and has chaos powers. Gerald was really into echidna civilization (what with the artifical Chaos, and all), and obviously had hedgehog data samples if he made Shadow. Who's to say Gerald couldn't have made a hedgehog with Chaos' data before finding Black Doom? Plus, Shadow says he thinks Sonic's the Ultimate Lifeform during the Finalhazard battle. Seems to me Sonic is Shadow's prototype. Still doesn't necessarily explain Sonic's speed, though...
 * Except that Sonic doesn't have innate Chaos Powers. Without direct access to at least one Emerald, Sonic has only his incredible speed. Shadow is the only entities capable of using Chaos powers without an actual Emerald in his hand, and even he prefers to use one anyway.

Where Sonic comes from, Rouge is equivalent to a Succubus.
Succubi are generally associated with bats, usually because they have bat/demon wings. She has an outrageously large rack. She comes on to the other characters moderately often. Just looking at her, don't you think it makes sense?
 * Which leads into this WMG....

Rouge is/was influenced by the remaining 1/4th of Morrigan
The portion attached to Belial eventually escaped, using Sonic's world as a stepping stone to get back home due to the high levels of ambient energy there. Cue run-in with Rouge/taking physical form as Rouge and there you have it. This explains Rouge's Jiggle Physics, the similarities in her costume, and why she's always flirting with everyone. If it's her essence in physical form, the reason why she hasn't fed on anyone yet is because of all the energy just floating around/the Sonic universe is so much Lighter and Softer. Or it's the reason she's always going after the Chaos Emeralds.

Sonic has a lifelong Phobia of drowning.
Whenever he comes in contact with too much water, his mind becomes overwhelmed with fear and he loses consciousness.
 * Perhaps it's the same for all characters with Super Drowning Skills.
 * He DOES in Sonic Underground, and had to overcome his fear a couple times.

Sonic the Hedgehog is THE GODDAMN Batman
Isn't it obvious?
 * Both are cultural icons
 * Both have pointy ears.
 * Both have neat gloves and boots.
 * Both have irritating kid sidekicks.
 * Both have starred in Lighter and Softer and Darker and Edgier media.
 * Both have been known to fight a fat guy with a pointy nose.
 * Both have encountered a thief which oozes Fetish Fuel.
 * Both have a TV series that is hilarious in its awfulness and is dominated by scene-chewing villains.
 * Both have an animated series that is critically acclaimed for its dark tone, serious storylines and brooding cityscapes.
 * Recently, Sonic was made a werewolf. Recently, Batman was made a Frank Miller character.
 * Both can (seemingly) breathe

Sonic is asexual

 * He just doesn't have the time to slow down for a relationship, which is why Amy is out of luck. There's a reason his only friends are animals who can almost keep up with him.
 * Explain his icky relationship with Elise. As far as I'm concerned, he's a reverse furry.

The "Tails Alone" mode of Sonic 2 and S3&K happens when Sonic time travels to the future in Sonic CD.

 * Each time Sonic goes to the Future in Sonic CD, the rest of the universe continues to exist in the Present. On one of these occasions, Dr. Robotnik decides to stay behind and take over the Present. Meanwhile, Miles "Tails" Prower has grown up hearing about the Legend of Sonic the Hedgehog--a mythological hero who has already saved Little Planet in the Past. A similar, modern-day hedgehog has also saved South Island and the Little Planet in the Present... before disappearing mysteriously. Tails learned to spin attack and spin dash by studying these legends. And when Robotnik builds the Death Egg, Tails is the only one in the Present who can stop him. (Because Tails is a fan of the Sonic Legend, he built a mechanical autopilot for his biplane that looks just like Sonic. Notice--when this "Sonic" flies the plane, he stares straight forward and doesn't fidget like Tails would. He is not the real Sonic.) Tails destroys the Death Egg, channels the power of the Super Emeralds and the Super Flickies, and returns the Master Emerald to Angel Island. Robotnik flees to Little Planet in defeat and travels to the Future himself, taking his chances with Sonic again. When Robotnik and Sonic return to the Present, the "Tails Alone" timeline is UNDONE. After all this, maybe Sonic doesn't understand why Robotnik kidnaps Tails and tries to kill him in Sonic 2 (8-bit). But, it all makes sense. Robotnik then rebuilds his machines to fight Sonic and Tails in the new Present, throughout Sonic 2 and S3&K, but this time around he crafts a new Doomsday Battlesuit, just in case.
 * How about I simplify this?: After the events of the original Sonic the Hedgehog, Sonic travels to the Little Planet to stop Dr. Robotnik's latest scheme. He chases Robotnik into the Bad Future, and Robotnik warps to the Present and leaves Sonic stranded there (as the Bad Future is assured, for now). Attempting to take over a world without Sonic, Tails steps in, trying to be like his idol he's heard stories about. Thus the "Tails Alone" mode of Sonic 2 happens. When Sonic makes his way back to the Present, the "Tails Alone" mode of Sonic 3 & Knuckles is just finishing up (as it's implied that the trilogy was one continuous story with no gaps). Sonic learns he has to destroy the machines in the Past to free the Bad Future, so when he travels to the Past, it erases everything that just happened while he was gone. Sonic catches up to Robotnik planting the devices to enslave the future, chases him back to the Present, and defeats him. He returns to earth, unaware of the adventures that happened without him. Sonic 2 8-Bit happens next, as Robotnik remembers what happened and captures Tails for revenge (and it still takes place on South Island). Then Sonic 2 (on Westside Island) then Sonic 3 & Knuckles happen normally, only now Robotnik has his battle suit in Doomsday (a level Tails couldn't access).
 * This whole theory is now completely jossed due to the fact that Sonic CD offically now takes place between the first two episodes of Sonic4. Which means, that the Tails Alone modes never happened, which in turn, allows Sonic AND Tails to be side by side during Sonci 2 8-Bit, like they should've been to begin with as evidenced by the level title cards! BRILLIANT!
 * SEGA (Ken Balough) actually said that's not what they meant when they said Sonic 4 was a sequel to Sonic CD, so it might still have happened between Sonic 1 and Sonic 2. But anyway, there's a bigger problem now. All of Sonic's time travel shenanigans have suddenly made it so that Tails can be the hero of Sonic CD, with Sonic and Amy both absent! I call alternative dimension for this one.

Tails was originally the Guardian of the Master Emerald
When the concept for Tails started out, he was destined for great things. At first, he was to be a Tanuki, a mystical raccoon/dog of Japanese folklore. That bore too much of a resemblance to for Sega's comfort, so the idea was changed.

Tails was then to be a kitsune, a mystical fox of Japanese folklore that grew a tail every hundred years until it reached nine. This explains the gender confusion (one of the cartoons translated Tails to be a girl) and the super intelligence. It also explains the two tails. It's not a birth defect, Tails is a hundred years old!

But being 1992, and the lack of Internet, American audiences didn't know what a kitsune was. Rather than try to explain it, he was transformed into an ordinary fox with two tails.

Yuji Naka said in an interview during Sonic the Hedgehog 2's production, that there was a secret level where you brought all the Emeralds to become Super Sonic. Later on, a level known as Hidden Palace was revealed, and at the end of the level was the Master Emerald!

But the level was Dummied Out however, lost to the cutting room floor. Hackers found the zone still existed (and it even made the cut in the recycled level select images in Sonic The Hedgehog 3), but playing through it revealed a Tails 1Up monitor.

People began to speculate. In the Japanese storyline, Tails saw Sonic land in the Tornado, was fascinated by it, and made some unauthorized modifications. Sonic was impressed and they've been together ever since. In the American storyline, Tails grew up being a fan of Sonic and thrilled at the chance to work alongside him.

But on both counts, he came out of nowhere. Was he a native of Westside Island? What was the deal with the two tails? It would've been less confusing to leave him as a kitsune.

People began to put things together, and speculated that the Tails 1Up monitor represented that Hidden Palace was to be a Tails only level, and that the roadblock at the end of the level that resembled the Master Emerald, really WAS the Master Emerald.

Ben Hurst, the writer of the Sonic Saturday Morning cartoon, had the idea to have Tails discover he had latent powers. This carried over into the Archie comic book series, where Tails was destined to be the Chosen One and do things greater than Sonic or Knuckles.

Could all this Chosen One talk tie back into his past design as a kitsune? Is Tails really as mystical as we think and was the true guardian of the Master Emerald? It makes you think..

Doctor Finitevus stole technology from Aperture Science...

 * And then improved upon it. Portals can only stick to certain surfaces and are of a defined size and shape; Warp Rings can be placed anywhere and how "open" they are can be controlled by the user. That, or the game was really popular in Albion and he decided to replicate/improve it.

Humans and other animals intentionally construct the levels for Sonic's use as a Super Hero

 * Sonic's first game isn't when he Jumped At the Call to become a hero. Sonic had been running around saving the day almost all of his life, and the original Sonic the Hedgehog is just when Eggman came into prominence. Because of his constant heroic efforts, humans and other animals construct special roads and pathways for him to traverse when he needs to, allowing him easier access to areas without having to run on busy roads used by everyday people, as well as being designed for his entertainment as a sort of sport for his and other fast running characters who might need to stop an evil plan to take over the world(Hence things like loop-de-loops). Springs and platforms are also added to the "Sonic Only Roads" by these people. Its Eggman that intentionally places spikes and other hazards as he is aware Sonic and other heroes use these roads, and can prepare and plan in advance. This explains much of the extreme Benevolent Architecture found in most of the stages. that said, there are exceptions to this theory.
 * Ancient ruins are protected as historical monuments, and as such don't have their architecture drastically altered for Sonic's use, explaining why levels such as Labyrinth Zone and Marble Zone are rather slow levels.
 * Compare Speed Highway's first segment to its last. The first drastically differs because as it is obviously as "Sonic Only Road", explaining why there are no cars on it aside from Eggman's robots. The final part of the zone looks like, for the most part, a normal part of the city. It also has normal cars on it, indicating that Sonic isn't intended to use this area for his Super Hero antics.
 * From Sonic Adventure 2, City Escape looks like a mostly normal City, complete with cars and parks. On the other hand, Radical Highway is drastically different as it is a "Sonic Road" that is still under construction.

This WMG is not for the faint of heart.
I have noticed that Dr. Eggman has a beach area in the Egg Carrier, and a swimming pool room. This implies that Eggman owns a bathing suit. Let that image forever haunt your nightmares/erotic dreams (if you're into that sort of thing).
 * I would assume that he would be wearing an old-timey swimsuit, which covers much more and is typically seen on old people in works of fiction.
 * This probably goes under Fridge Horror rather than Wild Mass Guessing.

The Current Metal Sonic is not the same as the one from Sonic Heroes

 * Think about it: Metal Sonic was taken by Omega and Shadow at the end of Sonic Heroes and wasn't even given a passing mention in the next game starring Shadow; then, he shows up in Sonic Rivals, lacking all his powers and higher intelligence and under Nega's control, and then shows up in the sequel under Robotnik's control, while Nega uses Metal Sonic 3.0. Now, why does Nega call his Metal Sonic a 3.0 when there was never a 2.0? Because the normal looking Metal Sonic from the Sonic Rivals series is a new one, originally built by Nega, stolen and reprogrammed by Robotnik. The original Metal Sonic was taken and put in stasis somewhere by Omega and Shadow who are waiting for the right moment to release him...
 * ...under new programming.

Metal Sonic's persoanlity survived and is in a new body
Think about it, by Sonic Heroes, Metal Sonic had technological capibilities on the level of Brainiac. So it would be safe to assume a fragment of his newfound nanotech could preserve his personality. When Eggman Negga first returned to the future, that fragment followed him, and took over Metal Sonic 3.0. When Sonic defeats Metal Sonic 3.0, he drops off the screen and is never seen or mentioned again. So one could think Metal Sonic staged his demise for both bodies to truly hide in the shadows and overthrow Eggman.

The Biolizard is Female.

 * Think about it, the thing produces eggs. Not to mention that female lizards are larger than males, so the Biolizard took that notion Up to Eleven. You may now proceed to be Squicked out.
 * Then consider the fact that in the fight against it as the Final Hazard, the eclipse canon is shoved up 'her' ass and 'she' is doing an awful lot of roaring and flailing...could this be a case of Getting Crap Past the Radar?

Robotnik wasn't trying throughout most of Sonic 2
It explains some of the pitiful bosses (Really, Robotnik? A drill car is the best you have?) and badniks pretty well. Right up until Death Egg, he wasn't fighting, he was stalling. All he needed was to keep Sonic busy until the Death Egg was launched. Robotnik planned for Sonic to get on board and everything. Silver Sonic and the Egg Mech were Robotniks only genuine attempts to kill Sonic that entire game.

G.U.N. knew that Sonic was not the one to steal the Chaos Emerald in Sonic Adventure 2
In Sonic Adventure 2, Shadow is mistaken as Sonic, and thus, Sonic is taken into captivity.

G.U.N. should have known who Shadow was, and should have been perfectly aware that wasn't Sonic, both for the fact that it's commander knew Shadow (somewhat personally, as shown in the Shadow the Hedgehog game), and that the two hedgehogs don't look much alike.

They did, however, know that Eggman was involved.

Sonic, normally, doesn't jump into things until Eggman makes his move and threatens people/the world. If G.U.N. had not captured Sonic, Sonic probably wouldn't have known anything was up until Eggman blew up half the moon.

G.U.N. captured Sonic early on to get him involved in what was happening. Sonic was able to escape fairly well, and able to rip off some metal to make a makeshift board to get away. The helicopter itself was there to help him get away, in hopes that Sonic would run across Shadow. Or, that Shadow would seek out Sonic, as the news was proclaiming Sonic stole the Chaos Emerald. Shadow would probably want to meet that other hedgehog.

Additional support comes from Prison Island and Rouge. Rouge is an agent for G.U.N., and knew where the Chaos Emeralds were because they told her. They let Eggman get those Emeralds as a gambit that Sonic would be able to stop him still, knowing that Tails, Sonic's closest friend, had the last Emerald.

They figured that both Sonic and Tails would have to work together to deal with Eggman and Shadow, which is why Rouge also happened to have that copy of the newspaper that said Tails received the Emerald as thanks for saving the city (from back in SA 1). This was so Tails would be sure to be involved. They couldn't be sure that Tails would show up on Prison Island, after all.

This is why we see no G.U.N. soldiers. They had robots because they were keeping up the ruse of trying to stop and capture Sonic, even though they knew he wasn't responsible. It would keep Sonic involved and determined to find out the truth, and distract Eggman while Rouge found out about Shadow.

After all, Sonic has a long track record of taking down Eggman and evil things he unleashes, and G.U.N. knew they couldn't break through the ARK in time to stop Eggman. They gambled that Sonic would be able to stop Eggman before he attacked the planet.

The reason that they simply don't ask Sonic to intervene is that Sonic is very much his own person. They also wouldn't want someone asking questions, such as who and what Shadow was. By manipulating him, G.U.N. kept Sonic focused on simply stopping the bad guys, and not finding out about who the bad guys really were.

Sonic is, essentially, Chaotic Neutral. He does what he thinks is right, no matter what other people perceive to be the good guys and bad guys. If G.U.N. had come out to Sonic, the hedgehog would have doubtlessly agreed to take on Eggman, but he wouldn't have gone all out on Shadow if he knew that Shadow had been imprisoned for over fifty years. Something like that, complete and utter restriction of freedom, would seem like one of the worst possible fates for a person like Sonic.

G.U.N. couldn't have Sonic worrying about moral quandaries. After all, in SA 1, Sonic is concerned with Perfect Chaos. He refuses to simply seal Chaos away, but wants to help and heal the creature. Sonic would have probably attempted to do the same for Shadow. By having Sonic act independent, all Sonic would know is that Shadow is a powerful hedgehog like him, who's helping Eggman and wants to destroy the world. G.U.N. wants Shadow out of the picture. Sonic wouldn't do that, especially if he knew about Shadow's past.
 * This totally explains why the Hell GUN didn't interfere by coming up to the ARK at all during Sonic Adventure 2 (unless you count the robots, but if they really cared you'd think they would send actual soldiers like they did later in Shadow the Hedgehog).
 * G.U.N. couldn't have admitted it was Shadow stealing the emerald even if they didn't want to frame Sonic. Why? Because they spent fifty years covering up the true nature of what happened on the ARK. Think about it. Gerald's diary said that the ARK was shut down under the premise of a "terrible accident," and when Sonic and his pals first arrive on the ARK, even Tails says the place was shut down because of an accident. This means that G.U.N. spent fifty years denying the existence of Project Shadow. Fast forward to the present day, where Eggman has released Shadow. If they come out and admit Shadow's existence, they have to deal with a whole new can of worms. First off, it would cause a big heaping mess of political trouble, with the president and other world governments demanding a full explanation. And then you have the public outcry. The general public would be appalled to find out the true nature of the "accident" that caused the ARK to be shut down. Especially family members and descendants of the people who were killed on the ARK. And if Sonic had publicly condemned G.U.N. for imprisoning Shadow the way they had, it would make people even more upset. It may even cause people to demand that G.U.N. be shut down, or it would at least cause a bunch of G.U.N. high ranking officials their jobs.
 * It's even possible that this WMG only applies to the most senior G.U.N. personnel. Chances are, most of their active work and combat force are simply too young to remember The ARK incident.

Rouge's "mistake" in SA2 was planned
Rouge becoming trapped in Prison Island in Sonic Adventure 2 seems to be a very ditz moment that serves only to show Shadow's motivations and give him an encounter with Sonic. However, this becomes a lot different in light of Rouge being a government spy. The reason she gives is that she was trapped in the security hold after defeating Security Hall's boss, Flying Dog. But, what if she and the rest of the military had planned it so that she would be "trapped" - in a very bomb-resistant location, in fact, probably underground, given its similarity to Iron Gate - so that the Dark Side's plan would fail, and G.U.N. could escape with the three Chaos Emeralds, all without revealing Rouge as an agent? Granted, she only had about an hour to put this plan into motion (counting Weapons Bed / Vs. Tails, and it later got shortened even further), so this was probably quick thinking on her part.

Alternatively, if you discount the idea that the room would be bomb-proof (despite that many structures still stand in Shadow the Hedgehog), it could even be a suicide mission to keep the Emeralds from Shadow and Eggman, or it could be a gamble for Rouge to learn more about Shadow's abilities to manipulate time and space (she even alludes to it after the rescue), which was her stated goal.

Eggman is lonely.
He just wants a friend, he's just doing it wrong. This is actually canon in the UK comic.

Eggman's speed is perfectly natural.
When someone is threatened by death, they are capable of superhuman feats, like that guy who threw a boulder away. Right there Sonic seems determined to kill him (it's the end of the game and a fat man was able to elude you, the fastest thing alive, all while imprisoning your animal buddies. Who wouldn't be screaming "IT'S OVER NOW, FATASS!") and does kill him in one of the possible endings. Eggman suddenly has a burst of adrenaline, and goes faster than Sonic's normal top speed. Now if Sonic was under the same conditions...

Sonic's eyes are turned green due to Master Emerald exposure.
In Sonic 1, 2, and 3K, his eyes are simply black. During the end of Sonic's story in S3&K, he's standing atop Tails' plane, next to the Master Emerald, for some time while Tails carries it back to Angel Island. At the beginning of Sonic 4, which takes place right after the end of S3&K, Sonic's eyes (or at least his irises) have been turned green.

Sonic's eyes were always green.
The Megadrive just didn't have enough blast processing to show it.
 * Probably canon, retroactively or otherwise. After all, Sonic's shoes were always supposed to have belt-buckles on them, and were made into stripes due to technical issues.
 * Jossed-Sonic Generations reveals that Classic Sonic is the younger version of Present Sonic, and that Sonic has the traditional look.

The reason there aren't any anthro NPCs.
The anthros simply have societies of their own. The backgrounds you see in the old Megadrive games? The anthros live there.

Eggman (his game version) is trying to take over For the Evulz.
Not in a stereotypical way though. Eggman knows he has the intelligence to take over the world,and he wants to see if he can. World domination is like a challenge, a game to him. That's why he's so damn Affably Evil-he's doing it for fun. Whenever Eggman acts crueler than normal, it's because he's getting a bit too into the game. Think about, if he truly had a lust for power, wouldn't he just shoot Sonic? Eggman isn't really evil, he's just very eccentric.
 * This...would explain a lot of the supposed Villain Decay, actually. Just not why he's doing stuff like unleashing the "God of Destruction", the "Ultimate Life-Form", Iblis, and Dark Gaia, the last one done by cracking the world into pieces. Of course, if he really is a little bit crazy/eccentric...
 * He probably doesn't realise how destructive his actions are. Being an Adult Child, he metaphorically plays with matches, thinking "I've got this under control". Only now does he realise that you don't mess with said matches.
 * This is now canon forever.
 * This could go further. Eggman may not have tried to conquer the world until Sonic came along. Why? He needs a foil, a challenge. G.U.N wouldn't "play his game", however Sonic would. Hence his regret when he thought Sonic was dead. Eggman is a big old Adult Child, who doesn't realise the extent of his actions. Metal Sonic rebelled because he saw this, and Nega hates the fact his parallel/ancestor is a manchild.
 * ...Um, what? He DID try to shoot Sonic many times, and attempted to kill him in SA 2. And he states in Generations that he likes to tell others what to do, heavily implying that he's genuinely interested in conquering the world.

The donor for the hedgehog DNA of Shadow is Sonic's ancestor.
Some 50+ years ago Professor Gerald needed a sleek, hedgehog form for Project Shadow. A hedgehog researcher decided to donate his/her DNA, but first performed some experiments surrounded Chaos Energy. This altered his/her genes so his/her natural hedgehog speed was amped Up to Eleven. However it skipped a generation and reached Sonic and any siblings he may have.

There are two Eggman Nega and Blaze the Cat out there.
The universe of the Sol Emeralds is, in a way, 200 years ahead of the normal universe. The characters in the Rivals series have parallels in the Rush series. However they suffer from Identical Grandson complex and thus appear exactly like their ancestors. Which is why Eggman Nega looks like Eggman, despite being his descendant.
 * Or alternatively, the Blaze from 06 is the Rush Blaze's decandant.
 * I thought that the Blaze from 06 was the same from Rush. See, when Blaze chose to be the vessel for Ibliss, she told Silver to warp her to another dimension. Blaze became guardian of that dimension's Emeralds due to her increased pyrokinesis abilities from Ibliss, but becomes cold and distant because she doesn't want to befriend anybody that could potentially lead to heartache and crying, thus releasing Ibliss once again. Come Sonic Rush, Eggman Negga and his future technology, had found Blaze's dimension and her Emeralds. Eggman Negga is the arch enemy of Silver and Blaze, as evidenced in Sonic Rivals, but since Ibliss had destroyed the future, he wasn't seen. Perhaps his amazing technology allowed him to escape to the same dimension where Blaze ended up so he wouldn't be killed by Ibliss' reign of terror. By the time Blaze had been warped there, Eggman Nega had finalized the plans to steal the Emeralds, which is why Blaze was appointed guardian because they knew Negga was a shifty looking guy.
 * Maybe the Rush parallel universe was a Mirror Universe, however Eggman Nega invaded and killed the Sonic and Eggman. Blaze was sent to that dimension to replace Sonic.
 * How about, there are two Negas and two Blazes. What you didn't know, is that there's also two Sonics, two Tailses(?), two Amys, etc. They have different versions: Chaos Dimension, the realm where the Chaos Emeralds are held and the majority of the series takes place, and the Sol Dimension, the world where you shipped around the world destroying Robot Pirates. It is accepted that the Chaos Dimension Nega and Blaze reside 200 years into the future of the Chaos Dimension, relative to Sonic. However, in the Sol Dimension, Nega and Blaze fight in the present, relative to Sonic. Going by that measurement, two hundred years into the past, Sonic and his friends roamed the Sol Dimension in all its Industrial Age Steampunk glory. This is backed by the fact that not only does the Sol Dimension have their own versions of zones in the Chaos Dimension, but mainly because the Sol Dimension Chemical Plant has no chemicals, all of it replaced with steam. This steampunk setting is complete with badniks with spectacles and wigs, and a boss that resembles a pendulum/grandfather clock. So in the end, Sonic and Blaze are not counterparts, neither are Eggman and Eggman Nega. Instead, Sonic is Sonic's counterpart, Blaze is Blaze's, and we have a double Negas.

Tiara will eventually be used
Pokémon did it with Leaf, and the Sonic games have already done this with Vector, so why can't Sonic? She will be redesigned, her age lowered to 14 - 17, and her role changed. She will appear for one game or have several roles as a help NPC. She will no longer by the high-sprung love interest of Sonic or the "match" of him, but still keep a similar role that differs from the other characters. Maybe a self proclaimed hyped up rival?

Eggman owns IGN
We all know the sort of reviews IGN gives to Sonic games. Eggman purposely creates Anti-Sonic Propaganda by using the reviewers at IGN.
 * He's also all those..."fans"...

Why Mephiles made Elise cry.
When Elise was killed in the 06 timeline, it released Iblis. However Iblis can only be released in his true form when the host suffers great emotional trauma. Mephiles learned her connection to Sonic, so he hired Silver and Blaze to kill Sonic,and later just doing it himself. Once in his true form,Iblis could merge with Mephiles to become Solaris.
 * This sounds interesting, but I think this theory needs more evidence. I just can't imagine SEGA's writers ever coming up with something as stupid as an apocalypse caused by one person crying, not in the least making an entire game set up around this problem.

Sonic and Shadow are actually related, and Eggman accidentally swapped places with Shadow 50 years ago.
First off, in Sonic X, we learn that our years are equivalent to Mobian months. So a Mobian year is 12 of our years, correct?

Now, if Shadow was on ARK 50 of our years ago relative to Sonic Adventure 2's time placement, then in Mobian years, that's about 4.17 years in their time(rounded up). Placing Sonic at about 11 or so. Which means he would have be alive at the time.

Eggman somehow ended up on Mobius, but we never learn how, just that he's been there for a while, and that Shadow is a Mobian based hedgehog that existed on Earth in Eggman's childhood (which we know Eggmna was on the ARC at some point, or at least knew about his Grandfather, depending on which continuity we follow, since the Archie comics claim Eggman was very young then, and other sources hint that he had to have been aware of them, given that his age is well over 50 years.).

So, a Mobian on Earth before Sonic and his friends were? One known Human on Mobius before anyone else? About the same time?

I think Eggy must have fooled around with something Gerald was working on, and somehow got himself and Shadow swapped, and no one just seemed to care much to get him back.


 * ...What Mobius?

Sonic is from world X-2 of Eversion
Because his eyes look like those of the enemies in Eversion when they're in world X-2.

Sonic and Mario take place in the same universe
Just different planets.
 * I don't think they can. Mario games take place on an alternate Earth. However, Warp pipes can lead anywhere, including other dimensions, other planets, anywhere except through time. So, we could say that the Mario Bros grew up on the Earth Sonic and co. live on, which would explain why no one is surprised by the Koopas when they are on Earth.
 * I also want to present my own here... The Chaos Heart is related to the Chaos Emeralds.

Finitevus represents/sympathises with the Unpleasable Fanbase, and those who have given up on the Sonic franchise.
They're always saying that the franchise "needs to die".

Shadow is Iron Man
An accident did occur in the ARK, but it was Shadow's own doing. When he found out Maria died, he tried to use Chaos Control to travel back in time before the accident occurred. However, something went wrong in the process and, as a result, caused the accident he tried to prevent. When G.U.N. found Shadow, he was in an unresponsive state and sealed away before he could awaken. For 50 years, his more recent memories slowly eroded away, causing him to believe that Maria wanted him to destroy mankind instead of save it.
 * I read that thinking you meant the superhero Iron Man, until I clicked the link and saw Black Sabbath. It does make sense in context!

Mighty the Armadillio was killed in action.
We never see or hear him again after Knuckles Chaotix, but the atmospheres seems as if he died.
 * Sega Sonic Arcade. feat. Sonic Ray the Flying Squirrel and... Mighty the Armadillo.
 * That game came out before Knuckles Chaotix.
 * Knuckles Chaotix was originally to be a game of second string characters from past mediums (Vector from Sonic's Jam Band idea for the original game's Sound Test, Charmy from the manga in 1992, and Mighty from the arcade title), with Espio as the new character and star of the show. Soon it was decided that Knuckles' star power would help sell more copies, but the character select menus keep Espio's name on top despite Knuckles getting top billing. Rumor has it Mighty's creator bailed and took the rights with him.

Tikal will be playable in the next Sonic main series game.
Tails was the Exposition Fairy in Colors, so why not?
 * Well, she was playable in several multiplayer modes for various games.....
 * I.e she will be playable in single player, and perhaps tag alonside sonic much like Tails did in Sonic 2 and 3, Because Tails gave hints much like Tikal, Omochao, Chip, etc, did. Since Tikal is the most popular out of those I mentioned, being an Ensemble Darkhorse (Being treated like a reccurer despite apearing in 5 games and an arc of Sonic X, only 2 in major roles, and having almost no merchandise) within the series, and much like Tails, so why not?
 * If the theory about her being Sonic's mom is true... Aww.
 * So, this means... Tikal Abuse vids all over?
 * Only if she's in the special stages.
 * Why only in special stages?
 * I meant only if she's in the special stages. Tails hate stems from him being more of a hinderance than a help in the Sonic 2 Special Stages.

Robotnik is a Species Surname.

 * Going with the ther'e all robots theory, i propose that Robotnik is a robot too. as for where he comes from, he could have been made by Buy-N-Large or Cybertronain in origin, or pehaps Gerald made him.
 * If he is Cybertronian, his current SA form is beast mode. his robot mode is closer to the Sonic the Hedgehog version.

the fifth player in poker night at the inventory is shadow.

 * obviously, he had to have had something to do recently. most likely knuckles told him about.
 * Doesn't really fit alongside the other characters there. I would guess Guybrush or Wallace or Gromit or possibly Bone.
 * Tycho and Heavy's games werent Telltale.
 * Well shit. Considering the fact that the player does not talk....maybe Gordon Freeman?

Big is a Pedophile

 * Explain.
 * He hangs out with two prepubesent girls a lot.
 * I think he's too stupid to be a pedophile.

Knuckles punching the Chaos Emeralds out of Sonic in Sonic 3 and Knuckles is a Brick Joke

 * A future game will have a villain who gets all seven Chaos Emeralds and go Super. No one will know what to do, then Knuckles will show up, punch out the Emeralds, and save the day.
 * This Troper approves wholeheartedly. It'd definitely be a nice change of pace from all of the Flanderization and demotion he's been subject to post-Heroes. Not to mention a CMOA and CMOF.
 * Totally. Sega needs to stop treating Knuckles like a joke character.

Sonic is a terrorist

 * In Sonic 2 he runs around wreaking havoc in casinos and oil refineries and S 3 K expands this to hydroelectric dams, carnivals and a new possible revolutionary form of energy (that's mobile no less) called the Flying Battery.
 * Considering the lack of not-robots, I would guess most of the places not already built by Robotnik must have either had all living things there killed and/or the people had escaped the level by the time Sonic gets there. Of course, this would very likely not have mattered very much to Sonic.
 * Also, the Flying Battery just means its an electric blimp.

Sonic killed a bunch of people when the Death Egg was destroyed

 * And not just because of the giant flaming chunks of metal raining down on the planet from orbit. The Death Egg is gigantic, too big for one man to need, plus lit windows and such are clearly seen. On board the Death Egg are scientists and researchers working with Robotnik, coming up with new badnicks and helping build them, working on miscellaneous projects and such. Now along comes a supersonic blue hedgehog running around either in the bosses room or the maintenance areas trying to blow it up. And he succeeds. Who's the real bad guy?
 * Doubtful. Eggbotnik has enough brains on hand to do it on his own, and if he did need somebody else to do thinking for him, he would probably just build robots to do the thinking.
 * Depends on how high in orbit the Death Egg was. If anything he could've created an asteroid belt of debris that could mess with the planet's gravitational pull.

Every Evilly Affable incarnation of Eggman is really Eggman Nega
After he killed the real Eggman, he accidentally dipped his mustache in brown paint and he lost his own clothes and had to wear Eggman's clothes.
 * Or he did it on purpose.
 * Eggman Nega's not Evilly Affable, he's a Complete Monster.
 * You can be both, you know.

Blaze and Percival are sisters.

 * Needs more Weird Time Shit in order to work.

Gawain did commit suicide
The back of the RC Knuckles racer, the Sonic Chronicles Guide, and several other things written after Sonic and The Black Knight state that Knuckles is the last, despite the existence of fellow echidna Gawain. Gawain almost killed himself. So he killed himself post-game.
 * Maybe he felt guilt after helping Eggman Mordred kill Sir Lamorak?
 * No, out of boredom.

The Silver seen in Rivals and Colors is a robot built by Marine

 * Marine built a robot? She can barely build a functioning boat.
 * Or maybe he was made by the Fourth Great Civilization.

Marine is lesbian

 * ....Evidence?

The Blaze from Rush and the one from the 2006 game are alternate universe counterparts
Basically, everyone from Sonic's dimension has an alternate counterpart in Blaze's dimension, and vice versa. The one who protects the Sol Emeralds and knows Marine is the counterpart of the one who knows Silver. As from why this Blaze is from the future and all... Uh, quantum physics?
 * Or maybe, they are family.
 * Or maybe Rush!Blaze's counterpart in Sonic's world is an ancestor of 2006!Blaze who looks different, the Blaze appearance coming to light in a later generation.

Amy was on her period during Sonic Free Riders
She was more arrogant and bitchy during this game than usual. Or so I have read.

Mobian Animals have extremely strong AT Fields
Explains a lot really.

Tikal is really a web footed tenrec
This would explain a lot. First, why is Knuckles the last of his kind when there are other echinas blatantly in view? And why does she have no toes?
 * Official art has shown time and time again that Tails and Amy have no toes either. And for why...

Tails is a birth defect
This is why he has two Tails and no toes. No wonder he broke up with Cosmo and Fiona! They didn't want their kids to lack toes or have two tails.
 * Fiona and Cosmo? I'm no expert on Sonic X, but didn't Cosmo kind of die?

The reason you don't see Big's toes is because he is wearing blue socks

 * ....But he lives in a swamp/rainforest. Why would he wear blue socks in that evironment?
 * They were once white, but turned blue because of the dirt.
 * Doesn't answer the question. Why is he wearing socks in a place that primarily consists of swampland?
 * To stand out. He likes the feel of soggy socks.
 * Because he's Big.
 * In most swampy areas, the grass grows really big, and there are tons of bugs. He probably doesn't want his feet to be super-itchy when he finishes up, since in sandals like those his feet would not only get wet, but also easily blistered, and he has less protection from ticks too.

Rouge is half-human
Just.. look at her.

Fiona Fox is possesed
Why didn't she go back to the good side? Because she's possesed.

Yacker really said he was from a far away soda and where flowers water them with dances.
Yacker was born on an island somewhere in the world of Sweet Mountain Zone. The ocean surrounding said island was of course made of nothing but soda. As for the rest of the sentence, this comic offers a very plausible explanation. Tails' translator didn't have any bug, after all.

The original Amy is dead

 * I think I know where you got this idea from...

Eggman can use Chaos Control.
Its how he was able to outrun Sonic,seem stronger than his body size should allow and never get caught.During the events of the first game,Eggman experimented with a Chaos Emerald.This led to him to becoming a second Ultimate Lifeform.

If you don't get the Chaos Emeralds in Sonic Colors, Dr. Robotnik steals Blaze's soul and becomes Robotnik Prime, and conquers Earth.

 * In the DS version, I presume.

The Story of the Tails Doll's Supposed Theme
We're all supposed to know that the Tails Doll's theme is Living In The City, right? Well, many people think it's Can You Feel the Sunshine. Now, why do you suppose that is? I'll tell you: Tails Doll felt weak using his real theme, and needed a better theme to become more fearsome. In comes Metal Sonic, carrier of the Resort theme. Tails Doll stole the theme from MS, thus becoming the monster he is today. However, in doing so, he also weakened Metal Sonic to the point where he himself needed more power in order to take on Sonic.

Come Sonic Heroes, and we see that Metal Sonic absorbs Chaos' power to become the Metal Overlord. If we take the previous paragraph into consideration, this was Metal's way of compensating for his power being leeched. Chaos had more than enough power to spare from two creatures merely connected to it, meaning if Chaos were there for real, things would have been a LOT worse off.

In short, Tails Doll steals Metal Sonic's power by taking his theme, and Metal Sonic steals Chaos' power to compensate. Any questions?

Shadow, Amy and Rouge are Aladdin, Abu, and Jasmine respectively in the Arabian universe

 * Sonic is Aladdin. Amy and Rouge could still be those characters though.

Shade commited the systematic hunting down of Knuckles Clan
i.e. She killed Tikal, Sinbad, and Sir Gawain.
 * Er....she was kind of too busy being stuck in the Twilight Cage to be in story books or in the world of the Master Emerald.
 * She did that when she got out.

Eggman suffers from multiple personality disorder.
On one side is the Affably Evil and almost Anti-Villain esque Dr Ivo Eggman.On the other side is the Complete Monster Dr Julian Robotnik.Both share the same memories,and both want to Take Over the World.However their reasons differ:Eggman wants to do it because he thinks he'd do a better job than the people in charge, while Robotnik wants to because enslaving everyone brings him joy.The two are constantly fighting for dominance:the former is in charge when he acts charming,and the latter is in charge when he nears Moral Event Horizon territory(such as trying to destroy Station Square with a missile)

Every universe and variation of Eggman(asides from the odd Mirror Universe) has this.In some universes such as Sonic the Hedgehog and Archie, the evil side is in total control. In others, the affable side is in total control(like Sonic X). Evilly Affable Robotniks like Adventures and Eggman Nega is due to a reverse of the game Eggman. As for the Bad Future we saw in Sonic CD? That's what happens if Eggman's good side loses
 * You're confusing continuties. In Games, Ivo is Robotnik's only first name, Julian is Sat AM/Archie only. And if we are speaking about Dr. Ivo "Eggman" Robotnik, the personality conflict should be reversed. Ivo Robotnik was the good doctor, who became Eggman after the start of villainous career. Cue egg-obsession, childish character, uncontrollable anger, desire to conquer the planet etc.

Shahra was meant to be a reccuring character
She was a sticker in Super Smash Bros Brawl.

Shahra and Merlina are the same character
Think about it. Both original characters, check. Both human, check. Both use magic, check.

Silver is now a completly normal hedgehog
At the end of Rivals 2, he loses his powers. It gradually took over him further and further to the point he lost sapience, sometime after Colors. But don't worry, Blaze absorbed his memories.
 * He's dead now, of old age.

Shadow and Rouge already are married.
That's why they don't appear in Unleashed and Colors.

Fang was created in responce to Snively
Wut.

Amy cut off her own toes and gave them to Sonic

 * ...She's a bit crazy, but she's not Cute and Psycho ....

Vector is an evil clone of Tails
He's Waluigi's counterpart as opposed to Rouge.
 * Expecting a counter? Too bad! VECTOR TIME!

Mighty never existed
He Never appeared in a canon game.

Metal Sonic's CPU is slowly deteriorating and has been since Sonic CD
Proof?: During the big race in Sonic CD between Metal and Sonic, Metal had to overload his circuits to achieve a greater speed than Sonic momentarily. This is done multiple times.

Over the years, his behavior have become more unpredictable and erratic. He has participated in racing events (Sonic R, Drift 2, Sega All Stars Racing), has been seen in Olympic sports (even figure skating), watching tennis matches (Superstars Tennis), reenacting Sonic's adventures (unlockable skin in Sonic Adventure), imprisoning his creator and taking his identity, blowing himself up to fuse with extra parts, ripping himself open to retrieve Chaos Emeralds, hiding inside of and taking control of other robots, mutating himself, showing signs of mental confusion, celebrating victory over Sonic by giving away Sonic's clothes and skateboard, and stealing lifeform data.

Metal is breaking down over the years, and will cease being functional in the near future. Neither him nor Eggman are aware of this.

In-universe, echidnas have the best eyesight of all the species on the planet.
Shadow and Sonic look nothing alike, but Amy and every single human that matters mistook them for each other. Mephiles and Shadow are almost identical (only differing in the color of their stripes and eyes), but from afar, with the glare of the computer monitor behind Mephiles, Knuckles could STILL recognise that Mephiles was not Shadow.
 * That would be pretty impressive, but it's more likely Knuckles simply recognized that Mephiles had a different voice to Shadow. Amy never gave Shadow a chance to speak before she glomped him, or she would have noticed he didn't have Sonic's voice. Also mannerisms, as Mephiles walked and moved differently to how Shadow would. So the point could be that echidnas are the most observant of all the species on the planet, and don't necessarily have the best eyesight.

Why Tails loses a life when Sonic wins.
Tying in with the above, in the Tails Story universe, Sonic challenged him to a race to every Chaos Emerald/Capsule in the game, and Tails can't turn him down. (Whereas, in the Sonic Story universe, he's content just to try to be where Sonic is.) Second, he's emotionally fragile and can't stand to lose, even to his best friend. Finally, he's subconsciously dangerously medium aware. As a consequence, whenever Tails finds that Sonic has reached the goal before him, he commits suicide, unwittingly trusting in the extra lives he probably has until he completes the level first. It's the only way I can think of to reconcile why it would make a difference whether he or Sonic gets to the goal first: He's not willing to live with a loss.

Blaze's life must suck.
Consider for a moment, the world in which Sonic Rush Adventure takes place in. Her world. A world that likely has more water than the Great freakin' Sea. Now, turn your attention to two things:
 * 1) Blaze has fire-based powers.
 * 2) She is a cat.

G.U.N. is defunct
It was not mentioned in Unleashed, despite there being an urban city level.

Sonic and Shadow can curl up like Real Life hedgehogs do...
...but curling up for a defensive purpose is their cultural equivalent of screaming like a little girl, so they only curl up offensively.

Rouge is a gold digger
think about it, in SA2B she is the love interest of Knuckles, who is the guardian of the master emerald; but in the later games Knuckles rarely mentions the master emerald and Rouge becomes the love interest of Shadow (who always carries a chaos emerald)

The Sol Dimension is a No Woman's Land
Just to rub the salt in Blaze's wounds.

Fan Mythology of the Sonic Game Universe and Sonic Team Universe as a whole
Okay, let's start out with the theory of the Chaos Emeralds being a manifestation of the concept of chaos. After the emeralds were made, some unknown life form, presumably a single cell, absorbed the power of them and became a god. The god decided to make a world. He did so, but the life forms living on it made it into a festering pit of darkness. The god created a creature (Dark Gaia) to destroy the world. The god decided that he would do better on his next try, but first made a creature (Light Gaia/) to protect the better life forms from Dark Gaia. He then made Chao, what seemed to be the best creatures fit for the planet, as they embodied innocence. He made non-anthros for the enjoyment of his "children". Some Chao liked the non-anthros so much that they tried to imitate them. This led to the creation of the anthros. The anthros are different because they are capable of corruption (a trait later passed on to pure Chao), have special powers, and go through more changes during maturity (the differences between Classic and Modern Sonic). The god also created Humans, who were more complex, but seperated from the Chao and Anthros until they found them milinniea later. The god (let's call him Thysis) then discovered two new planets (Dark Comet and Planet Wisp). Thysis sent Chao to the planets in hope for colonization. The Planet Wisp colonizers became the Bablonians (their appearances came from the birds brought there, and the Extreme Gear came from their facination with the Wisps' powers of flight). Unfortunately, the Black Comet colonizers became corrupted by the comet's powers, and became the Black Arms. Thysis was fortunately able to delay the Black Comet's arrival near the planet. He looked for more planets in the universe, before realizing that he had to handle one project at a time. He sent out a Chao to colonize other planets. The Chao went mad with power and became a tyrant (Kaiser Greedy). Thysis tried to destroy him, but couldn't find the strength to kill any of his children, after the tragedy that was the first project. Greedy was sealed away instead. Thysis knew that Greedy would return, so he created a race of Star-Knights (Ristar's species) to fight him off if he should return. One night, Thysis fell asleep and had a nightmare. With him in the nightmare was a child, who was sucked into a dark abyss. Suddenly, Thysis got many complaints of nightmares, usually featuring a dark wizard (Wizeman). Thysis soon had an idea. He went to sleep, and when he got to the world of Nightmare, he balanced it out by making one side Nightopia. He also sent a beam of light into the depths of Nightmare, hoping that it would turn into a positve Nightmaren (Ni GHTS). Thysis also created a physical system that balanced the power of each side of the Dreamworld and the Gaias, Morning Land. Thysis realized that being a god is very hard, and he could not protect his children alone. First, he summoned a large community of Echidnas, and told them about the Master, Super, and Chaos Emeralds. He told them to protect the emeralds with their lives, and christened them 'The Guardians'. Then, Thysis produced an Egg from his own genes. He gave the one inside the Egg great powers over the emeralds, being able to harness their energy easier than most. He gave the being inside the Egg a big heart, like his, and a strong will, so he would not meet the same fate as Greedy. He then realized that he would be happier if he protected the world by instinct instead of by command. So with great reluctancy, he placed the Egg on the planet, and made himself invisible to all life forms that would come in contact with the being. He then spent many years attempting to get a Chao to copy a human. After several generations,  was born. Thysis then set his plan in motion by hatching the Egg. Once it hatched, Thysis produced a tag labeled  for the Hero to read when he was able to read it and ready to start   world-changing journey. Over the course of the years, Thysis set up all of  grand adventures to prepare   for what lies ahead. One day, all the heroes created by Thysis will team up to stop the destruction of the Sonic Team Universe, and learn of their true creator. Crazy Taxi and Space Channel 5 likely take place in human civilization, while the protagonists of Billy Hatcher are likely Chao-Humans. You got me on Chu Chu Rocket and Phantasty Star.
 * Or alternatively, Thysis did not create humans or non-anthros, (insert actual god here) did.

Shadow is going through a lot of emotional character development in his first few game appearances.
Shadow was created in a lab. He may have the mental capabilities of an adult, but in terms of his experience with the world, he's still a very young child when the G.U.N. raids the ARK 50 years prior to the events of Sonic Adventure 2. He does what he can to try and save Maria, who is his best/only childhood friend. She ends up getting shot to death by a G.U.N. agent right before his eyes, and with her last breaths, sends Shadow to the planet below. It's not stated how long it takes, but sometime after Shadow lands on the planet he gets captured by G.U.N. and placed into suspended animation. Time passes, and eventually his creator's grandson releases him. If you think about this from Shadow's perspective, he probably didn't experience the passage of time. This means that while the events of Sonic Adventure 2 take place 50 years after the ARK incident, in Shadow's mind it has probably been no more than a week or two since Maria was killed right in front of him. Many people in real life would probably need some sort of therapy to help cope with witnessing such an ordeal, but Shadow probably didn't get any since G.U.N. at the time just saw him as a dangerous weapon, and what kind of weapon has feelings? During the events of Sonic Adventure 2, Shadow is still going through the grieving process as if Maria's death just happened the other day. Because for him, it was just the other day.

At the end of Sonic Adventure 2, everyone finds out from the diaries that Maria's death sent Professor Gerald off the deep end. Gerald was probably the closest thing that Shadow had (or knew of, at the time) to a father figure, so seeing the results of his 'daddy' going insane on top of the loss of his childhood friend was probably too much. The reason he shows up with amnesia in the Sonic Heroes and Shadow the Hedgehog games is because his brain deliberately made him forget everything to preserve his sanity. As the events of those games progressed, his memories gradually returned at a rate slow enough that he could handle it a little at a time. So it's only in more recent games that we have been able to see what Shadow's personality is like when he's not grieving or an amnesiac.

Theoretically speaking, Shadow has the potential to be the most powerful character in the series.
It all comes down to how he uses his Chaos abilities. He has potential beyond what even SEGA may realize. His basic Chaos ability, Chaos Control, is established to warp and distort space. According to Einstein's theory of relativity, space and time are an interwoven fabric. It's pretty much impossible to distort one without having some influence on the other. SEGA has played with the separate possibilities of warping through space and traveling through time by using Chaos Control, but there is so much untapped potential. Relativity not only establishes the interwoven nature of space-time, it also states that gravity is a distortion in the fabric of space-time. If applied correctly, Chaos Control could potentially be used to manipulate and control gravity fields by distorting space-time, similar to the alien artifacts that SEGA needlessly created to control gravity in Sonic Riders Zero G.

If Shadow was able to exploit his Chaos Control to the fullest potential, he could use gravity itself to be the most powerful character in the series. He could create a gravity field around enemies and completely dominate them. An enemy that can't lift its own weight is just a sitting duck, waiting to be killed. A gravity field around himself could cause his attacks to land with the force of something weighing several tons. Or he could do the opposite, and lessen the effects of gravity on his own body, allowing him to hover or levitate. At the most extreme, he could eliminate gravity completely, causing objects (or people) to fly to pieces because their molecules are no longer gravitationally bound to each other. On the opposite extreme end, he could concentrate gravity to the point that it forms a black hole.

How much of this is actually possible remains to be seen.

Hedgehogs have an innate ability to learn things easily
In real life, some people have ways they learn best. Some learn by listening to an explanation, some by doing an activity, some by just watching it be demonstrated. In the Sonic universe, hedgehogs have a natural ability for picking up new skills just by watching someone else. The most obvious example comes from Sonic Adventure 2. In the Hero's side story, Sonic encounters Shadow after the first stage and boss fight and after a few words Shadow leaves the area using Chaos Control. Later in the game, Eggman traps Sonic and shoots him outside the ARK inside a capsule rigged to explode. After a moment of internal monologue where he wonders if he can pull it off, Sonic manages to use the fake Emerald to escape the capsule by using Chaos Control.

Character last names
Sonic
 * Hedgehog (Archie)
 * Needlemouse
 * Parolouzer

Vector
 * Chaotix

Cream/Vannila
 * Yamamoto

Tails (of Sonic X) was Subconsciously possessed by the ghost of a mobian who believed in reinacarnation in the hours prior to Cosmo sacrificing herself
isn't it obvious, he sees a mirage of Cosmo and somehow believed it was real.

Chip actually
It happened to Tikal, so why not! The reason Mr. Pickle did not tell Sonic is because he is short and Pickle thought he was a kid.

King Boom Boo was a crocodile in life.
Because of the teeth, and he lives in Egypt. All other ghosts in the series have been actual species.

After 06, Blaze was indeed returned to the future, but...
the Ifirt killed (or kidnapped) her shortly afterwards.

an explination of Tikal's (and possibly Chaos's as well) death(s)
Shade was inside the emerald and killed them both. Or alternatively, the Master Emerald has no air holes.
 * Now in fanfic form.

Charmy's stinger is cybernetic
He's a male bee.

Cream is the reincarnation of Tikal and Maria
There're all cute pacifists.

Sonic is what keeps Eggman from getting bored.
In the Bad Futures in Sonic CD, Eggman's machines and mooks are rusty and broken down, because without Sonic, Eggman didn't see a point in advancing forward, due to the fact few, if any, seemed to challenge him. Colors is him simply accepting that his chances of winning are slim to none, but by god if he isn't gonna try to win.

The Chaotix from Knuckles Chaotix and the Chaotix from Sonic Heroes onwards are diffrent
The Knuckles Chaotix ones hail from the Sol Dimension. If you really want to get technical they could have originally hailed from the future (or they may even be their Sonic the Comic versions), but sealed themselves there to stop a demon.

Merlin from The Black Knight universe was that universe's Eggman.
I have nothing to back up my theory, except this cute fanart of Eggman!Merlin and tiny Merlina. (Art from this site)

Amy collects Sonic dolls.
She really loves Sonic.

Cream's real name is Misty
See the Dorklybits video "Tails Can't Die".

The Iblis somehow wound up in Mighty
During the retcon of 06, the Iblis went to Mighty. That's why we don't see him anymore.

Tails has No Biological Sex
Tails has No Biological Sex, but prefers being called male. However, he will refer to himself as female in latin languages to avoid confusion with "Tails" being a feminine word in those languages.

When Classic Eggman ...
He eventually got smarter and smarter until he became the Duke of Solenna. Later, a sample of his sperm went to the SATAM universe to create Sally.

All of the Sonic characters have a counterpart in Blaze's dimension.
Eggman has Eggman Nega, so it could be expected that the other characters have a counterpart as well, and that we've already seen some of them. Blaze is either Sonic or Knuckles, while Marine is definitely Tails.
 * Silver is Big and the Iblis or Ifrit is Froggy.

Eggman's been taking it easy on purpose.
Generations plot follows on from Sonic Colours, wherein Eggman finds the Time eater in space. He goes back into his own past, and recruits his past self to go through this plot. However, he already knew it was going to fail. After all, he had been here before, when he was younger, and his future self came back to visit him and help him out with the Time Eater. Both Past Eggman and Future Eggman know they will fail already, but they have to go through with it because You Can't Fight Fate.

However, upon his return to the past, Past Eggman knows that he will go through all these schemes which he knows will fail, as there's no reason to endure the scheme in Generations otherwise. But since he also knows all his schemes up to that point, and knows they're innevitable losses, he puts no effort into them, knowing full well that for the time loop to occur he has to fail all those times. So he's giving it minimum effort, just enough to convince Sonic that he's a threat, and rather than actively trying to kill Sonic, he just goes about enjoying the fun of the fight, rather than seriously fighting, hence why Sonic wins so often. Sonic has literally had it easy, because Eggman knows he cannot win for the timeline to work until he's done with the Time Eater in Generations.

The Hedgehog DNA donor for Project Shadow was a descendant of Lancelot
Hence Shadow's resemblence.

Game Sonic is a prince like Sonic Underground Sonic
And he also returns Amy's feelings, but hasn't told her because he needs to make sure she'll be a good co-ruler before he can take the relationship further.

Why Maria was more powerful in Shadow the Hedgehog than Sonic Adventure 2
She had these powers all along, but she refused to show them in Sonic Adventure 2.

The Blaze from 06 is a paid impersonator of the Rush version
Like an Elvis Impersonator.

Robotnik died at the end of Sonic 1
The reason he outran Sonic was that he was a ghost.

Eggman Nega was never from the Sol Dimension in the first place
Eggman Nega came from the future to try to get Blaze. When he found out the one from Rush was not the one from 06 (via genetic test), he went back to the future.

Cheese is Chaos
1. Cheese does not appear with Cream in SA:DX
 * Cream and Cheese never seem to intentionally separate meaning that sonic advance 2 takes place after sonic adventure

2. Cheese is incredibly powerful
 * Cream is able to use Cheese like a weapon in almost every game she's playable in, He obliterates everything

3. Chaos is implied to originally be a Chao

4. Chao's can reincarnate when they die happily
 * It seems that when Chaos died he was at the very least satisfied

5. Cheese never seems to age
 * As he is around Cream at nearly all times he should be aging rapidly

6. Using an obscure method involving reincarnating twice Chao can, in fact, become immortal
 * These particular Chao are called CHAOS Chao

Chip was just a vessel for Light Gaia
Chip used to be an ordinary chihuahua dog. However, Light Gaia did the same thing that Dark Gaia did to the phoenix. Ultimately, Chip really did die in the battle against Dark Gaia, but not Light Gaia. In reality, Light Gaia is an Eldritch Abomination just as bad as Dark Gaia.

Rouge is just human
The progressive commercial shows Flo as a cartoon character through Sonic's eyes.

Sonic still has Dark Gaia in him
It is never stated that Dark Gaia's influence has left him. Fits with Blaze still having Iblis and Ifrit.

Sonic is the son of Lola Bunny and Roadrunner.
Bugs Bunny and Lola get married and decide they want to have a kid, but they find out that Bugs is infertile so Roadrunner becomes a surrogate father. The baby inherits both parents' physical traits, as well as Roadrunner's speed and agility and Bugs's personality.

The Metarex Saga is a fictional adventure written by Chris, because he wants to have another adventure with Sonic and Co.
Hence Chris' sudden competence, most of the characters being Out of Character (Well, more than usual for Sonic X) at one point or another, and the sci-fi theme... It is, quite plausibly, something a young teenager would think up.

Vector is Charmy's legal guardian.
Charmy's parents are nowhere to be seen, Vector's the only legal adult in his life. Before you bring up Tails as a counter-example, it's possible that Tails is legally emancipated; he's shown to have his own house in Sonic Battle, and he has the maturity and skills to support himself, being an engineer/inventor might be an actual job that brings food to his table. Can you imagine Charmy living on his own?

The storybook games, Mario and Sonic At The Olympic Games, and other such spinoffs are the results of Silver taking antidepressants after all those terrible things in the main games
Notice how he always seems to be happy in them, yet in the main and portable games he (in order) watched cities being destroyed, humiliated on a regular basis, lost his girlfriend to a self-commited human sacrifice to a flame creature, rewrote time but did not get the girl back and the cities are sill in ruins, and most recently getting crushed by a big boulder... Blaze still loving him? Necrophilia on the part of Silver and Blaze's mangled, charred, bloody, half-eaten corpse (thanks Ifrit). Eggman Nega's occasional appearance? Silver using his mementos of him as a punching bag. The 06 and Rush Blazes appearing to be the same? His refusal to accept 06 Blaze's demise. Rouge and Omega as 1-dimensional bad guys? I don't really know, maybe they never really warmed up to him or he accosiates them with Iblis and Ifrit too much.

Sonic and his friends are all a single species.
That is, Sonic and his friends are supposed to be anthropomorphic animals with the same basic body shape (including noodly appendages, rounded bodies and toeless feet), but the "species" they're supposed to look like is purely aesthetic. This explains why they can be paired up with characters that are supposed to be a different species. Also...

Eggman is the same species as Sonic and his friends.
Much like Sonic is an anthropomorphic hedgehog, Eggman is actually supposed to be an "anthropomorphic human". His "human" characteristics are basically Turned Up to Eleven: mainly his intelligence is greatly exaggerated and so is his bastard tendencies.

The Ifrit is the Sol Dimension
Whatever Ifrit absorbs/eats/etc goes in the Sol Dimension. This is shown by Nega being from the future here but from another dimension in the Rush games. This explains why Blaze was at Sonic's party: he had to claw her out of the Ifrit's bowels.

Knuckles inspired Capcom and Cyber Connect 2 to create Asura from Asura's Wrath.
Both are loners, have anger issues, rely on punching, they can fire projectiles out of their fists, have exceptional super strength, etc. It's pretty dang obvious.

Eggman Nega died of starvation
He was trapped by rubble in Sonic Rivals 2 and never seen again outside of the Mario and Sonic games.

The Echidnas modeled Emerl after Chaos and the Chao
Emerl can copy the attributes of other beings just like the Chao, and gets progressively stronger with the power of each Chaos Emerald he gains just like Chaos. Chaos, the Chaos, and the Emeralds were once in close proximity to one of the Echidna Tribes. Emerl and Chaos also both have blank eyes.

Sonic's dimension and Blaze's dimension are nigh identical, but 200 years apart.
There's two Blazes; one residing in an alternative dimension's present as a princess, one from the future as a partner in justice to Silver. Two Eggman Negas appear alongside the Blazes, with the same malicious intents. The duplicates in Sonic's dimension are 200 years into the future as seen from their Sol Dimension counterparts. The proof in this theory comes from taking this formula (where a character in the future of Sonic's dimension has a counterpart located 200 years in the past and one dimension apart) and applying it to Sonic's realm. Let's take a look at Chemical Plant: Latest and greatest in technology at the time, alternating paths that spiral around each other, and the energy source of the plant is used as a gimmick in the level. With Chemical Plant in mind, let's take a look at Sonic Rush Adventure's Machine Labyrinth; latest and greatest in techonology at the time (being the 1800's), alternating paths that spiral around each other, and the energy source of the plant (steam) is used as a gimmick in the level. Let's not forget Crystal Cavern, which looks loads like Quartz Quadrant from CD, how Plant Kingdom looks oddly familiar to Mushroom Hill from Sonic and Knuckles, and certainly not how Sky Babylon looks loads like Sky Sanctuary from Sonic 3 & Knuckles. With all of these elements and such taken into account, I have come to my conclusion: '''Sonic and Blaze are not counterparts. Neither are Eggman, or Eggman Nega. Sonic has a counterpart in Blaze's dimension, but he lived 200 years ago, fighting steampunk badniks against a (probably) hilariously British Doctor Ivo Rrrrrobotnik.''' The whole counterparts thing the Eggmen were babbling about was Eggman Nega's lie, because his name blatantly states that he is completely against Eggman's ideals, and instead of world domination, he wants world destruction - hence, Eggman Nega. And to cover him up, he lied and told his foolish ancestor that they were counterparts, while he attempts to figure out what is actually happening.

Another reason for this theory existing is that if Sonic and his friends were 200 years into the past, then that would mean Steampunk Metal Sonic, and tell me that idea doesn't sound bitchin'.

Sonic was raised by Eggman as a Tyke Bomb
This is based off of his origin story from Fleetway. Sonic was born somewhere, adopted and raised by Robotnik as an experiment. In fact, Sonic was one of his first attempts at taking over the world. He had a fascination with Hedgehogs that he shared with Professor Gerald, so he took a regular old Mobian Hedgehog and did experiments on him until he turned blue and gained Super Speed at a young age, essentially training him to be his ultimate weapon. Fortunately, Sonic realized what Eggman was doing and vowed to stop him. The fact that he was always an experiment explains why his eyes changed color between his pre-pubescent and teenage years, and why he occasionally can't speak during certain events (such as Classic Sonic being unable to speak during Sonic Generations, and Modern Sonic being unable to speak during the Progressive commercial).

The biggest reason Sonic doesn't ever talk about his history or origins is because deep down, he is ashamed of himself for actually trusting Eggman for his formative years, and almost helping him take over the world if it weren't for the fact that he still had free will even after all of his... well, experiences. He's also worried that others learning about where he came from would cause them to distrust him or assume that he was The Mole this whole time.

Sonic Adventure 2 was going to be Metal Sonic's origin story, and Shadow was the substitute.
This theory was partially inspired by this video, particually Metal Sonic being the only playable character hacked in that doesn't cause the game to glitch the victory jingle. Then consider the fact that Shadow is often referred to more as a robot than an organic android. Isn't it a little strange that it would only take a few tweaks to the story to wedge Metal Sonic in Shadow's place, considering they're both made by the Robotnik family (and don't get started on the Fanon of Shadow rebuilt by Eggman) and misplaced identity issues?

Sonic Chronicles is the prequel to Sonic Rivals 2
While the anthros were, Eggman somehow found or created Ifrit and used it to conquer the world. When the furries  Afterward, Robotnik rules with an iron fist and either clones himself or has a child which is Eggman Nega, or Eggman Nega's ancestor. Ifrit kills Robotnik, and plunges the world into chaos. A couple of centuries later, Silver is born. This Silver is the same one that's in Rivals, and the ending of Rivals 2 prevents Chronicles from ever happening, which means that Shade and the rest of her clan are still sealed away.

The Chaos Emeralds are literally a physical embodiment of the concept of chaos
Perhaps before the dawn of Sonic's universe, there was nothing but a garbled mess of colorful nothingness. Just swarms of meaningless forces swirling about through an endless void...

Then, all of a sudden, some 'green' chaotic forces managed to smash together and create the Master Emerald, which had a bit of sentience. Upon realizing what process caused it to exist, it brought together all the chaotic energy and organized it by color, forming the Chaos Emeralds. However, when the Emeralds all came together, Chaos Control happened, sending blasts of "organized chaos" every which way and caused the so-called "big bang".

Now that the universe existed, the Master Emerald happened to teleport to the nearest planet with life on it, along with the Chaos Emeralds...

...But enough of the possible origin story... Let's get to the evidence:
 * The Emeralds have the ability to control time and space because the laws of physics do not apply around them, being made of pure chaos in a universe of order. This can cause even the user's craziest wishes to come to fruition. As Tikal said, they turn "thoughts into power".
 * The Emeralds scatter about after they're used. This may be because such large amounts of chaos energy being used weakens the continuity of physical reality, and therefore, causes the Emeralds' coordinates to be 'corrupted' and sent to some random location.
 * The special stages could be areas that are generated by the Chaos Emeralds themselves due to their instability. These strange places are remnants of what the universe was like before there was order (although with little bits of order in that there are 'rules' and physics in special stages).
 * Their 'chaotic' nature could also have something to due with the inconsistency regarding their number.

Everybody can use Chaos Control.
Shadow doesn't have any innate Controlling powers, only training. Sonic could pull it off in Sonic Adventure 2 thanks to sheer force of will in a life-or-death situation. You don't have to be The Chosen One involved - Tails and the Robotniks have powered all manner of devices from the emeralds alone. Of course, if this is true, then it makes you wonder why people don't just teleport everywhere, since even fake Emeralds with similar properties will work.
 * Building that kind of a fake emerald (all the same properties, but reversed polarity or whatever) requires inventive genius on the level of Tails or Eggman, which is presumably rare. Eggman rarely holds on to an emerald long enough to study it (he tries to use it immediately and has Sonic right on top of him the moment it happens); Tails had the entire stretch between the first Sonic Adventure and the second to build his, leaving one person in the entire world able to make such a thing. Presumably he doesn't want that kind of power multiplying; his continued aging backwards makes that kind of thought process more and more unlikely, but also makes new Chaos Emeralds more unlikely.
 * In the anime, the Metarex were able to mass-produce knockoff Chaos Emeralds (which memorably gave us Dark Super Sonic), so...yeah.
 * Clearly, GUN hasn't been pursuing this because the GUN Commander is deeply unreasonable about anything relating to Project Shadow. Within GUN, pitching for a new Chaos Project would likely be career-limiting at best and terminal at worst.
 * Here's a fun experiment: go back and play Sonic Adventure 2. When Amy busts Sonic out of prison, you can see that the walls of his cell are literally covered in what looks like very complex mathematics equations. Quite simply, Sonic saw Shadow do Chaos Control once, and once he had enough free time, he figured out exactly how it works. This is a particularly odd scene because they make a point of showing Amy staring at all the equations in wonder but never reference them later or give any real indication of what they were meant for. The only logical conclusion is that Sonic figured out how to do Chaos Control. Whether or not other people could, though...
 * Wait. You seriously think SONIC wrote all of that stuff on the cell wall? Be serious.
 * Sonic isn't that smart. That cell, in-game, was hinted to be Professor Gerald's former cell.
 * Gerald was executed in that cell. Watch that prerendered cutscene; there's text behind him.
 * So it's assumed by most that Sonic read AND understood those detailed mathematical equations on the wall?
 * It's possible that it's a susceptibility thing related to the individual. It's like being able to do maths: almost everyone can do it, but some people are far better at it than others.
 * Sonic's thought processes are sped up just like his metabolism. It explains how he can think and react at high speed, as well as how he can keep up with Eggman mentally despite Eggman having a 300 point IQ. It's not that he was able to understand the equations better than anyone else; it's just that, in the time it takes someone else to glance at it, he's already read it in depth and is beginning to interpret it and think it over in a way that would take a non-superfast person hours, just like the speed reading ability the Flash sometimes displays.
 * No, it's not. Not at all. It's assumed he was able to do it for the same reason as Silver (pure desperation), and also because he had a fair bit of experience with Chaos Emeralds by then.
 * Silver was able to do Chaos Control in the 2006 game just out of pure desperation. But since the Reset Button got hit at the end of the game, it might not still apply.
 * Just because the events... unhappened... doesn't stop them from still applying. Anything that happened in 06 had to be possible, even if it was later undone. (That also includes the existence of Soleanna and human-filled cities.)
 * Soleanna is definitely real, even after the Reset Button Ending.
 * This Troper was the first person to take a screenshot of the paper Rouge had in Sonic Adventure 2 (depicting Biolizard) and put it on the internet (I know because I spent years looking for it previously). Apparently, Biolizard had an organ that allowed the use of Chaos Control. We can also assume that Shadow has this same organ. Silver and Sonic's access to Chaos control is a mystery, but Silver's could be explained in multiple ways.
 * Indeed. While having an Emerald allows anyone with the sufficient willpower to access Chaos Energy, Shadow is one of two beings able to access it without an Emerald. Having an emerald does allow him greater control, however.

Chaos Control is really getting its power from the Speed Force
The ones most capable of using Chaos Emerald power are incidentally super-speedsters, who are also capable of totally supercharging on it to become even faster. Technology can emulate this effect but only by using the blueprints of the Ultimate Life Form.
 * Explain Silver in 06 then, he was one of the slowest characters in the game and relys on psychic powers, but is shown to be just as good as Sonic at using Chaos Control
 * Chaos Control can also bend Space, as Sonic's first use of it is to escape from a sealed pod, and in fact seems to instantly displace himself back onto the ARK, rather than when Shadow used it when confronting Sonic, where the Control carried him across the field, past Sonic, at incredible speed.

The universe runs on Spiral Energy
According to Sonic Adventure, the Chaos Emeralds are unlocked when they are used with The Power of Friendship. This can be an allegory for fighting spirit, A.K.A. Spiral Power. It has also been proven that. Aside from that, Sonic's Heroic Willpower prevents him from being hypnotized. This explains the vast amounts of parallels between Kamina and Sonic and Tails and Simon, and pretty much everything about the Gaia Colossus

Moar evidence for this theory - "Human" Boota is all but the spitting image of a Sonic-style anthro-(pigmole). Going by the comic histories, the "radiation" that mutated normal Earth animals into Mobians was in fact an explosion of Spiral Energy, explaining both the Mobian's rapid evolution and their notable lack of horrifying deformities. This explosion may or may not have happened shortly after Gurren Lagann's Distant Finale.

]].

Chaos Mechanics
OK, so this is basically my theory about how the Chaos Emeralds and the Chaos Force in general works in the Sonic Universe, taken from in-game usage and the lore of the Sonicverse.


 * As we all know, Chaos Emeralds are like infinite batteries, storing a bottomless amount of "Chaos Energy" that can be used to power machinery or empower creatures with the ability to focus them. The energy can also be stored in other objects to act as a power source when the emeralds themselves are not handy or too valuable to spare. The energy an be stored in "lesser" gems, and in animals. GUN uses their emeralds to mass-produce Chaos Energy-filled gem-batteries for their robots, which they call Chaos Drives, and Robotnik irradiates Flickies and uses them as a combined power-source and easy A.I.
 * The idea that both the Chaos Drives and Flickies are full of Chaos Energy is supported by SA 2's Chao Garden. Chao are deeply linked with Chaos, and lived for who knows long at the Shrine of the Emeralds. They react quite easily with Chaos Energy, which is in both the Chaos Drives and the Flickies you rescue in SA 2. However, after interacting with one once, they drain the energy from the power source and are empowered in a specific physical by the energy. More on Chao later.
 * Chaos Energy only appears in Sonic the Comic and made its way into Fanon, but it isn't canon. The energy given off by the Chaos Emeralds isn't specified to be any specific type of energy in the games, or different from any other source of energy. Also, its implied in the games that the tiny animals are more of computer brains for the robots, and not an energy source like the English translations assumed (such as Sonic the Comic).
 * Yes, but if they are charged with energy, that would explain why both the Chaos Drives and the Flickies cause similar reactions with the Chao. As for the Chaos Energy; whoops, I didn't quite know the exact place it has in canon. So rather then emiting Pure Energy, the Emeralds emit energy, but the kind of energy changes depending on what it's being used for?
 * Chaos Energy is effected powerfully by emotions. There's many ideas behind why this is (the Emeralds are sentient, Chaos Energy is really Dust, etc.) but the fact stands. This is reflected in the prayer used by Tikal and Knuckles on the Master Emerald. "The Servers are the Seven Chaos"(emeralds) "Chaos is Power, Power is enriched by the Heart. The controller is the one who unifies the chaos." Basically, a person who is focused on one aspect of their emotions can control the Chaos Energy into one of the many powers we have seen from them. This is all over the place: in Sonic Adventure, Chaos was only able to focus on his rage and pain and drew the power of his negative emotions out of the Emeralds, becoming an enormously destructive beast made out of pure liquid malevolence, while Sonic drew on the other, positive power of the Emeralds and became Super Sonic, a more controlled, less crazy super-mode. The Karma Meter of Shadow the Hedgehog is another representation of this aspect of Chaos Energy; it becomes an uberdestructive blast when Shadow is enraged, and manifests as Chaos Control when he's feeling less like causing wanton destruction. The building of the karma meters is emblematic of Shadow focusing his emotions, "unifying the chaos".
 * The Chao come in again here. Anyone who's used SA 2's Chao Garden enough will know that Chao change a lot depending on how they're treated. Chao that are tended to exclusively by Hero characters and treated nicely become shiny and angelic, while Chao that you abuse, and tend to with Dark characters become evil little imps. The emotions surrounding their upbringings changes their mindset and thus changes their appearance.
 * This is also where I should mention that Chaos Energy does not only come from the Emeralds. Or if it does a lot of it is ambient in the Sonicverse by this point (since you can't destroy energy, of course). I say this because Shadow, at least, is shown to be able to use Chaos Powers without any Chaos Emeralds to his name. Case in point: Shadow The Hedgehog's last action stage, after Black Doom takes all the Emeralds, Shadow is still able (and has to) use Chaos Control multiple times throughout the stage. As a skilled Chaos user, he draws on Chaos Energy ambient throughout the area and uses it after sufficiently focusing his thoughts.
 * Jossed by Sonic Battle. Shadow's explanation is he has Maria in his heart, so he no longer needs Chaos Emeralds, also Sonic Battle is when Shadow learns how to use Chaos Control without Chaos Emeralds.
 * Of course if, as Sonic Adventure says, positive emotions amplify energy more than negative ones (Sonic using the positive energy to go Super), then maybe his previously-negative emotions couldn't use the ambient stuff as effectively. Hence, he gained the ability only once he let go of those emotions and used his positive ones of Maria instead.
 * OK, tell me when Sonic Battle happens in the timeline. Seriously, I don't know where to fit it in. But since Shadow does learn to use Chaos Control without the emeralds late in Sonic Battle, well that just reinforces the point that they can be used without the emeralds: note that in both instances, Shadow says that it's his love for maria that strengthens him and allows him to do what he does. "Power is enriched by the heart".
 * From all the possible evidence, Sonic Battle could only canonically take place after Shadow the Hedgehog.
 * On Super Forms and Rings. My guess as to why people need to keep collecting Rings to maintain super forms, outside of the obvious gameplay reasons, is that even with all the Emeralds in one's control, stuff like Chaos Control or Super Modes are not exactly stable. Super Modes are basically filling one's body with a lot of Chaos Energy, far beyond one's ordinary capacitance for the stuff, and actively using that energy to produce flight, invulnerability, and incredible speed. When Sonic is in his Super Mode, he's constantly hemorrhaging Chaos Energy all over the place and expending even more, in order to use his powers, so most likely he can't refill his energy as fast as he drains it, even with all Eight of the Emeralds (they may have infinite energy, but there's a limit to how fast the current is). The Rings are therefore used to stabilize the whole process. The energy shooting all over the place is conducted by the metal ring and sent looping back around, presumably back into Sonic, kinda like an electric circuit. However, the level of energy conducted by the ring is enough to melt the sucker after a full second of exposure (gold having a relatively low melting point), making it crucial to keep collecting rings, as without them, there's no way Sonic (or anyone else with a Super Mode) would be able to maintain all those powers at once.
 * Incidentally, this is why Tails needs the Super Emeralds to achieve a Super Form. He's charging himself and a bunch of Flickies at once, so he needs to be able to channel that much more energy to do it.
 * I just think Tails is inexperienced with the Emeralds.
 * True, that's also a factor.

Nega Wisp Energy takes away an anthro's powers
Hence why Tails did not fight in Sonic Colors.

Chaos Energy can only be properly used by a living being.
Eggman constantly failed in his past attempts when he had the Chaos Emeralds because he always used them in his machines. None of them ever displayed the abilities that any of the "super" modes did because they weren't alive. It took him a while, but he finally figure that out.

When Eggman came up with his biggest scheme in Unleashed, he set up a half-hearted plot to ensure Sonic would go super and allow him to use all of the Emerald's power to awaken his true objective.
 * Super Metal Sonic from S3&K would like to speak to you.
 * As an Eggman-brand robot, wouldn't Metal Sonic have a small animal inside it to process the chaos energy?
 * I didn't think Mecha Sonic was able to properly harness the Master Emerald, given that it had to stop every 20-30 seconds to recharge.
 * He just ran out of rings.
 * Perhaps the requisite is not living flesh but a self-aware mind. Mecha Sonic, as Eggman's Dragon in Sonic and Knuckles, may have been given such a level of consciousness.

Low-size, low-quality Chaos Emeralds are very common: they're what keeps those Floating Platforms in the air.
They're also responsible for the Asteroid Thicket orbiting around Earth (Mobius, whatever) seen in Doomsday Zone from Sonic 3 & Knuckles. Chaos Emeralds are capable of levitating landmasses, as evidenced by Angel Island and the Master Emerald. Comparing the smaller platforms to the entire Angel Island, it's obvious that the Emeralds levitating these platforms only have a tiny fraction of the energy of the more famous emeralds, hence why Robotnik hasn't tried powering his machinery with them yet.

The prescence of Chaos Energy is the reason there are so many anthros.
Normally,only one intelligent species(in our case,humans) can exist on a planet-and even if there was more they would've killed the other one. Chaos Energy allows multiple intelligent species to survive

Chaos Energy
I know that there is a WMG above on Chaos Powers, but I fear that if I alter it, it'd just be put in a separate WMG anyway. Now, we have seen Shadow and some other characters use Chaos Control without an Emerald. In Sonic Battle, he says it's because he has Maria in his heart, other than me thinking that's a campy Hand Wave, Black Doom most certainly had nobody in his heart and could use Chaos Powers from my memory. Another thing I must bring up, Sonic was able to use Chaos Control with an artificial Chaos Emerald, which had less power than a normal one.

Why Shadow can do this? Simple. Chaos Energy is like radiation, it can grant the person powers, Chaos or not, when exposed to them for a long time. Assuming that Shadow held onto his Emerald until Sonic Battle or for some other long period of time, he was exposed to enough so that he could abandon it. Super Forms are just when a character forces the radiation inside of them, which is why Super Forms can use Chaos Powers without having to carry them around all the time. Another person who suffered Chaos Mutation is Tails. Think about it. In the original Sonic, there were six in total, when you meet Tails, a seventh emerald appears. He obviously gained boosted intelligence and a second tail from the exposure.
 * Except that the first instance of Shadow using Chaos Control without an Emerald was at the end of the White Jungle stage of Sonic Adventure 2, when he warps in and saves Rouge, sans Emerald.

The Super Emeralds will return in Sonic the Hedgehog 4: Episode II.
Just like how you can get the Super Emeralds by locking Sonic the Hedgehog 3 into Sonic & Knuckles, collecting the Chaos Emeralds, and visiting the giant rings during the Sonic & Knuckles levels, when you play Sonic 4's second episode, the game checks to see if you have data from the first episode and collected any Chaos Emeralds, then allows you to play through the game with the opportunity to collect the Super Emeralds.

Likewise, the Super Emeralds will NOT return in Sonic the Hedgehog 4: Episode II.
...And will instead appear in an Updated Rerelease with the two games combined.

There's more than one Emerald shrine on Angel Island.
I mean, if the only thing keeping your floating island from crashing into the ocean is a big glowy rock, wouldn't you want there to be a couple of back-up shrines for it to sit in, just in case something happened to the one the Master Emerald is currently in? Not to mention it would explain why it isn't in Hidden Palace zone in Sonic Adventure and its sequel. Not sure where it is in the first Adventure, but the desert it's in at the start of the second one certainly looks a lot like Sandopolis Act 1....

The red coins in Sonic Colours were meant for a Scavenger Hunt
Or some sort of prize thing...

The reason why Chaos Emeralds weren't the main focus on Sonic Colours...
Because Eggman already had them and hid them away from Sonic in a place of irony: A Video Game!

Regarding the Chaos/Sol Emeralds, and The Verse.
In Rush and Rush Adventure, many comparisons are made between the two sets of Emeralds and the North/South poles. Perhaps it's a literal comparison-- then, of what? For Rule of Cool, I've conjured up the following crackpot theory: The main world and the Rush world are on two ends of the entire Sonic multiverse. I envision a vast Dyson Sphere, with every world, every alternate timeline, every seperate continuity drifting in a massive void. The "prime"-verse Chaos Emeralds and the Sol Emeralds keep the void stable-- if the balance were to shift, then the entire Continuity Snarl would come apart at the seams.

The Super Emeralds aren't actually Canon. Likewise, Super Knuckles(and the similar others) aren't either.
A major thing that points evidence to this is Sonic Heroes. What happens when Sonic, Tails, and Knuckles get the Chaos Emeralds? Only Sonic goes Super. Knuckles should've gone that way too. Tails obviously can't, since he needs the Super Emeralds. Yet Knuckles didn't. Because he never could be in the first place. This would explain why somehow Silver could, despite having no ties to a Chaos Emerald other than being given one by a freaking Monster. Perhaps it's linked to hedgehogs canon-wise? Who knows for sure. It's the biggest oversight made by Sega, not to mention how badly they shot down nearly everything awesome about Knuckles in the first place. He's gotten a main character role in zero Canon console games. (Black Knight had Sonic go to an Alternate Universe after all)
 * Well, a video for an early build of Sonic Adventure did curiously show 14 Emeralds... it wasn't a transition effect either!
 * I do believe a lot of it falls under What Could Have Been. However, that never came to be, so my theory isn't currently jossed just yet.(wouldn't mind if it was)

Also, this means Super Tails isn't canon either by default. Super Silver is canon, argueably, but his ability was written out thanks to a timey wimey ball. As for anyone who beat Sonic 2006 would know.
 * Well, I have a theory about this. For someone to share their Super form, the person they share with must be the same species as the original user.
 * The only problem with this theory is... Amy. Even Mecha Sonic could use a type of Emerald(Master Emerald in this case) to go partially super. She can't harness the powers of the emeralds at all. She's the only hedgehog that can't. In a similar sense, Blaze is the Token Girl for Super Forms in gameplay. So why can't Amy be allowed to do that? If she can pull out Time Stops in multiplayer mode of Sonic Adventure 2(yes, I know it's not canon), then they could easily write the ability in for her to use a Chaos Emerald.
 * You misunderstood. I meant each time the emeralds are used, all the people who use them should be the same species.

How the chaos emeralds got to where they are in Sonic Adventure 2
It's simple: at the end of SA 1, Sonic just left them in Station Square. Think about where the emeralds are in SA2: GUN has three, Rouge has one (Which can be thought of as GUN having four), Tails has one (which was given to him as a reward for saving Station Square), Robotnik has one, and the last one is in a bank. My hypothetical sequence of events goes as follows:

Sonic leaves all the emeralds in one place in Station Square. Later, the city finds them and holds onto them. Later, they hold a ceremony and present Tails with the yellow emerald. GUN notices this and realizes that Station Square has the chaos emeralds, and requisitions them. This accounts for five of them. The white one may have been one of the ones given to GUN as well, only to be stolen by Robotnik between games. However, there's another possibility worth considering, namely that the white emerald fell off whatever crumbling overpass Sonic left the emeralds on and Robotnik recovered it at a later date. Something similar may have happened to the green emerald as well, only instead of Robotnik it was found by a random looter who put it in his safe deposit box.
 * In fact, G.U.N. probably gave Rouge the Blue Emerald so she could bribe her way into Eggman and Shadow's good graces.

Amy tracks Sonic by using Chaos Emerald Energy.
Lets think about this for a moment. Amy inexplicably seems to always be able to find Sonic. The guy moves faster then the speed of sound and likes to travel. The odds of her being able to know where he are extremely low. She also seems to always confuse others for him (Shadow, Silver, Werehog Sonic). What do all of these people have in common, besides being guy hedgehogs? They use Chaos Emeralds at some time or another. Why she still doesn't go plowing into them anymore? After the first time, she's able to tell the difference between them and Sonic. She probably doesn't realize she's doing it, though.

A theory on Shadow's Chaos powers
Sometimes he is shown using his Chaos abilities with one or more emeralds in hand. Other times he is seen using them when the known locations of emeralds make it impossible for him to be in possession of one. I've seen fans debate this many times, saying things like he doesn't need any emeralds at all, or that the scene from Sonic Adventure 2 where he rescues Rouge is evidence that he needs at least 3 emeralds to reach space via Chaos Control. This is my personal take on Shadow's abilities:

Shadow is perfectly capable of using his Chaos powers without any outside influence. He doesn't need any emeralds to use his power. But his abilities are at their most basic if he relies on his own energy. Shadow has the ability to draw power and energy from the Chaos Emeralds, and just being close to one is enough to tap into its reserves. Distance is a factor in this ability, and the closer he is to the emerald, the easier it is for him to access its power and vice versa. In addition to distance, the number of emeralds he is close to is also a factor. If he's near 7 emeralds, he can go into Super form for example, and if he's only near one, he obviously can't. However, one emerald is clearly enough to get to the ARK from the surface of the planet.

The one thing that's not clear about his abilities is the distance factor. How far away from an emerald does he have to be before the effort required to draw out the Chaos energy outweighs the energy received for his effort?

Presumably other characters such as Sonic have an ability like this as well, making it a natural ability for some. But considering that Shadow was created in a lab, for a project that was supposed to be a living weapon, I believe this ability is strongest or enhanced somehow in Shadow.

The shields in Sonic Heroes are the modern designs of Super Knuckles and Super Tails
This is pretty self-explanatory. In the "Classic" games, Super Knuckles and Super Tails just glowed (Well, that's how glow effects were done, anyway). They didn't change color, they simply glowed. If that was done in Sonic Heroes, where glow effects are actually possible, you wouldn't be able to tell the difference between their normal and Super forms at a glance. People have looked into the game files, and found evidence that this is correct.

The good AND bad ending in Sonic CD is cannon
This is why you race Metal Sonic in the bad future in generations. Sonic ran through sonic CD getting the bad endings, then (as the credits for the bad ending show) went back in time and set right what went wrong.

Chaos energy is actually a mass effect field
It explains everything. Sonic and other characters like him are biotics. They use biotic charge to move fast, warp for abilities like chaos spear, and mass-reducing fields to keep Eggman's huge airships and Angel Island afloat. Chaos emeralds contain masses of eezo in their crystalline lattices and are able to enhance a biotic's abilities. Gold rings are disposable kinetic barrier generators, and the bigger teleportation rings are miniature mass relays.

Sonic is a time lord
The time stones are a Tardis. I'm sorry, the game has time travel, I can't help myself
 * I have to add, Sonic is the Doctor, Eggman/Robotnik is the Master. The Master died around the time of sonic 3 and came back as Eggman.

The lyrics in the JP/EU version of Metalic Madness Bad Future (Sonic CD) is Eggman talking to the player as a result of Timey-Wimey Ball
In Sonic CD, Eggman conquers the Little Planet via the use of Time Travel va the Time Stones. Hence creating the duel futures that are possible in Sonic CD. By the time you've gotten to Metalic Madness (the last level) it's all but possible that Eggman's gained omnipresence from this time travel (and being able to exist regardless of which Future your in) and has not only seen Sonic beating him, but has seen through the forth wall and seen the player.

Let's look at the lyrics: "You can't do anything"/"So don't even try it, get some help"/"Don't do what Sonic does..."/"Sonic, dead or alive, is m-m-m-mine".

Let's openly assume that Eggman is the one speaking these lyrics. It doesn't make sence for him to tell Sonic to get some help or even refere to him constantly in the second person. So, we could come to the conclusion that Eggman is, infact, talking to the player to lower his or her moral prior to the final boss which, given that it's rather low in the panthion of Sonic final bosses, is his only weapon against the player's final assult.
 * This troper always thought it was Metal Sonic to rationalize the way the voice sounded. He was basically an evil, metallic Sonic, meaning he might have had enough personality to gain an attitude geared towards being an overall jerk and sore loser. In short, Metal Sonic's mocking you from somewhere in the level to keep you off your feet when you fight his master because he's sore about losing the race you had with him.
 * But he's already been destroyed by this point. That makes no sence...
 * You seem to forget Metal Sonic is a robot, and can be rebuilt atleast to the point of functionality before Sonic arrives. And before you say Robotnik didn't have enough time, I have two words: Egg Fleet.
 * That makes no sense. If Eggman rebuilt Metal Sonic, then why didn't Metal help Eggman fight Sonic in Metal Madness?
 * There is also the fact that Metal Sonic might not have been destroyed, and just too badly damaged to assist Eggman in Metalic Madness zone. All of the other Sonic imitators that have appeared in games have been shown as having been destroyed to a point of being completely unrecognizable; Silver Sonic exploded into nothing, Mecha Sonic was destroyed by Knuckles, blowing up into several pieces. Metal Sonic, on the other hand, crashed into a wall and fell off of Stardust Speedway, shattering his quills in the process but otherwise being whole. This leads me to believe that Metal Sonic survived the race, and it is possible for him to have provided his voice talents for the song.

Sonic Underground was not originally a Sonic show, but retooled into one.
The concept has little to nothing to do with Sonic, so I can't help but think that the show was originally about three original characters using music to fight an oppressive overlord (and possibly find their mother), and either Executive Meddling had the show retooled into a Sonic one, or the makers were told to make a Sonic show and decided on their own to recycle the premise.

Since Sonic's character is mostly intact, it could be possible that the original concept had a Brother-Sister Team of the characters who became Sonia and Manic, and Sonic was added to make it a trio. Likewise, Knuckles was added to give the show more Sonic flavour. Robotnik on the other hand simply took the place of a generic evil overlord.


 * So? Sat AM has little to do with Sonic, too. Sega's Sonic was never a member of a team of freedom fighters who fight to free the world from a Robotnik who has already conquered it. The concepts and backstories of Dic's Sonic cartoons were just random like that.

Chemical Plant is actually the Death Egg under construction.
I got the idea from this. Even though that's just a fan game, the Death Egg in that game actually uses Chemical Plant's tiles. Therefore, the "chemical plant" is just a big cover up, the parts of the level Sonic goes through is the outside of the Death Egg and the exterior is actually hidden under the level, being constructed.

Metropolis Zone used to be a lush forest.
In Sonic 2 Beta, screens of the missing Wood Zone have eerie comparisons to parts of Metropolis. Since the idea of Time Travel was tossed around with the development of Sonic 2, then perhaps Metropolis is what Wood Zone was torn down to become?

Big the Cat was originally going to be a cow at some point in development

 * Or maybe a hippo.

Blaze the Cat actual characterization is actually glimpses of her original role as the princess of Soleanna in Sonic '06
Not only her character actually debut during the development window of Sonic '06, but both Blaze and Elise also share core similarities that point that Blaze could play perfectly the role of the princess of the game, in the span of one year you had two characters that:


 * are princesses.
 * were cursed with or related to fire (Elise as a monster can, Blaze as a pyrokinetic, fact that can be easily tied in with Iblis)
 * had emotional problems that were related to the plot somehow (Elise was not allowed to cry because of Iblis, Blaze says she is not allowed to express her emotions in Sonic Rush)


 * played some sort of a love interest role (Elise in Sonic '06, Blaze in Sonic Rush as hinted as being a "implied Love interest" toward the end, characterization that stuck with her as seen in later games)

Not only that but lots of elements in the Sonic Rush series actually have similarities with elements found in Sonic '06


 * The Sol emeralds can be seen as the custom gems in Sonic '06
 * The Sol prefix can be found in lots of things but especially in Soleanna and Solaris
 * The scepters (Jeweled and Darkness), of both games.

Both characters share the same basic concepts, hinting the Blaze might have had her development transfered from Sonic '06 to Sonic Rush, Blaze's actual characterization is actually glimpses of her original role as the princess of Soleanna in Sonic '06, not only that but scrapped concepts of Sonic's Story in Sonic '06 could have been recycled in Sonic Rush.

Sonic Heroes' Hang Castle Zone is based on the Stone Tower Temple.
There are a lot of things Hang Castle has in common with Majora's Mask's last dungeon.
 * They are haunted.
 * They are found very late in their respective games.
 * They are set outdoors.
 * They have gravity-flipping mechanics triggered by attacking something.
 * The music changes depending on if the stage is right side up or upside-down, with a "trippy" version when upside-down.
 * They have eye motifs. (Flags in Hang Castle, Various paintings and statues in Stone Tower)
 * There is one point in both stages where you need to float over a strong updraft.
 * There is a statue that resembles the games' antagonists when turned upside-down. In Stone Tower, it's a man with an open mouth when right side up and Majora's Mask when upside-down. In Hang Castle, it's Dr. Eggman when right side up and Metal Sonic when upside-down.

However, there is no random statue of a hand pointing upwards next to a phallic spire in Hang Castle. Nevertheless, just as the Stone Tower has a popular theory about its builders challenging the goddesses, Hang Castle also seems to have a strong feeling of unholiness and blasphemy around it. I may look into this later.

On the other hand, the haunted pirate ship in Sonic Rush Adventure bears no relation to the one in The Legend of Zelda: Phantom Hourglass.
They were released so close to each other as to be Dueling Games. There's no way they can have all the similarities they have without it being a coincidence.

Tikal, Chaos, Jet, Wave, Storm, E-102 Gamma, and Emerl were going to be in Sonic Colors, but were Dummied Out
Their names can be found as save names on the Wii version, depsite not appearing at all on DS.

Robotnik's appearance and alternate name is loosely inspired by (the chorus of) The Beatles' I Am the Walrus
I'm sure this has been joked about many times before, but since it's not on this page... well, he is the Eggman, and his moustache and corpulent build is suggestive of a walrus. Goo goo g'joob.
 * Not really a WMG, since it was confirmed, like, ages ago, as of the original Sonic The Hedgehog. Originally there were a lot of Beatles references in the game, but SEGA execs wanted to make the series stand on its own, so many of the references were cut out of the game. "Eggman" and the walrus 'stache are leftovers.

Sega has been trolling hardcore Sonic fans since the Genesis days

 * Sonic the Hedgehog 2: Tails' AI, especially in special stages.
 * Sonic the Hedgehog CD: American Kirby Is Hardcore soundtrack for US version.
 * Sonic 3 and Knuckles: One Game for the Price of Two.
 * Sonic Adventure Series: Very buggy, slow outside of Sonic, Tails (in the first game), and Shadow's stages.
 * Sonic Heroes: Shadow's return feels cheap, Lighter and Softer
 * Shadow the Hedgehog: So Bad It's Good
 * Sonic the Hedgehog 2006: Compare the tech demo to some actual gameplay footage.
 * Sonic Unleashed: Werehog stages, which start out fun, but get really old, really fast
 * Sonic the Hedgehog 4: Modified Sonic Rush Series engine, Post-SA Sonic model.
 * Sonic Colors: Nintendo Exclusive, Mario-esque level design
 * Sonic Generations: HD Exclusive, only Sonic is playable, Mario-esque level design and incorrect physics in classic levels, Classic is written and designed to be a bit too cute.
 * Aha! But it's been confirmed for the 3DS, which...wait, does that count as HD or not? But still, Nintendo! Although, the 3DS version is different from the 360 and PlayStation 3 versions, with the main difference being that it's all 2D and Modern Sonic is based on Sonic Rush Series...which a lot of "fans" are complaining about...okay, you're right. Oh well.
 * Problem, Fan Dumb?

The whole original game is a hallucination of a drug-addicted marathon runner

 * Sonic is inspired by the man's pet hedgehog, the only thing that truly still loves him, and therefore the perfect animal to manifest as himself in his hallucinations.
 * Everything is so colorful because, well, he's on a drug trip.
 * The enemies are a combination of all of his appliances (which, in his insane mind, are out to get him) and the insects and animals he finds around and outside his house.
 * He needs to keep collecting rings because his marriage is falling apart, but his wife is the only thing that encourages him to keep on living; if he loses his ring, he dies.
 * Dr. Robotnik is his father, who keeps trying to stage an intervention, but the man sees him as trying to rob him of his happiness.
 * The special stages are what happens when he shoots up again, causing him to temporarily lose ALL of his focus on reality.
 * The Chaos Emeralds are his grip of reality during his drug trip. That is why at the end of the game, if you fail to collect all of them, his "father" will be juggling them around, just like his juggling relationship with his dad. The TRY AGAIN is a simple means of his brain telling him to take more drugs to be happy.

The Earth in the games is displaced in space and/or time from the real one.
Several continuities suggest this, such as Archie's "aliens dropped genetic bombs on the planet" story. The games themselves seem to accept this. In Shadow the Hedgehog, maps are seen in G.U.N.'s headquarters showing the planet... and its structure is vastly different, including a detached Africa. SEGA may reject the name "Mobius" from their canon, but the reality behind it remains.

The events in the Sonic the Hedgehog games happen in the far-future of the world in Girl Genius.
Sonic and his walking, talking animal friends with extraordinary powers are the descendants of various constructs in Girl Genius. Dr. Robotnik is a Spark, which explains his superhuman skill with building machines and robots, and also his ludicrous world domination plans and penchant for melodrama. GUN is the eventual descendant of the Wulfenbach Empire; the various hovercraft and mecha they use are high-tech descendants of the airships and 'clanks' seen in Girl Genius. The Chaos Emeralds are ancient Heterodyne artifacts whose original purpose and means of manufacture have been lost to time.

Physics are meaningless.
None of the characters, human hedgehog or otherwise seems to be harmed by gravity or G-forces. On this planet, Hedgehogs are bipedal, lanky, and multi-colored and every single animal (even some of the non-anthro ones) in this game seems to have magical properties. This isn't earth, or even our universe, or even a universe based on ours, the laws of physics are drastically different. Especially since several of the characters are shown to be able to breath in space. Therefore, in this universe, air isn't required for living beings, and maybe earth has no atmosphere at all, which would explain why characters can run so fast without the air ripping them apart through friction.

Gravity works differently, which is why no-one is hurt from falling and can openly defy gravity, and is also why big headed animals and big bodied characters like Eggman can stand without falling over.

Contact works differently which explains how Tails can move his tails without them tangling or hitting eachother, it explains why rings and items just dissapear and also explains clipping issues with some characters.

Energy also acts differently. Everyone knows energy cannot be created or destroyed, so how can the chaos emeralds GENERATE unlimited amounts of energy, where Blazes sudden fireballs come from and also why shadow can use up his chaos energy when in theory this is impossible.

And just as an idea, in this universe E=MC2 is different somehow, the result being that matter is transfered into tiny amounts of energy that most creatures can store inside themselves (possibly as chaos energy). This explains where Amy keeps her hammers, where tails keeps his weapons in Sonic Battle and where all characters keep their rings/chaos emeralds. It also possibly explains why Super forms use up rings, since they need to keep a constant storage of Chaos Energy.
 * Perhaps its not that the laws of physics are meaningless, but the existence of Chaos Energy allow people to override them. Life there just has Bizarre Alien Biology.

Sonic Unleashed happens directly after another already known Sonic game
Sonic already has the Seven Chaos Emeralds at the start, and has already overthrown Eggman. Likely canidates include Sonic Rush Adventure, Sonic and Tails return home with the seven emeralds, Eggman builds a space station, and Sonic already has the emeralds so he crushes him. Another one would be Sonic Chronicles, as long as 2 doesn't come out. Super Sonic single handily overthrows Eggman, having gotten the emeralds from the Twilight Cage, and that's where the game picks up. And then there are the people who place it in between Sonic 2 and Sonic 3. The space armada is just a highly stylized Death Egg, and the entire game is an alternate ending. The fact that Knuckles nor Shadow nor any of the new characters show up just adds to the theory. As for Amy, it depends on when you place Sonic CD in the timeline.
 * I think you might be on to something there. What plane does Tails use in Sonic Unleashed? The TORNADO-1. That's right, not the Tornado-2 that he uses from Sonic Adventure onwards. The Tornado-1, the classic plane he uses in Sonic 2 and Sonic 3 & Knuckles.
 * Uh, it's possible that Tails was simply feeling 'retro' and decided to use the basic original design for the Tornado complete with the red paint, and decided to call it the Tornado-1. Also, the Sonic Unleashed plane is capable of the transformation technology Tails did not perfect until Sonic Adventure 2 (not the first one--remember, "no landing gear"?).
 * Unleashed would have to take place after SA2 for the simple fact that in SA2 Eggman seems completely unaware that the Earth and its people can survive being shattered, while in Unleashed he's obviously banking on it.
 * Wait... I can't remember. Which came first, Sonic Unleashed or Sonic Chronicles: The Dark Brotherhood? If Brotherhood came first, it's definitely immediately after that, considering Sonic had all the Emeralds, AND Eggman already had the world under his thumb.
 * I don't believe, from what I've heard anyway, that Chronicles referenced Unleashed, but I do think it was released after. It makes more sense if Chronicles game after Unleashed, though.
 * But the world sure doesn't look like a global Eggmanland. The people sure don't look opressed. Heck, he released Dark Gaia so he could make a city for himself. Besides, Tails has the old Tornado in Chronicles, despite the fact it clearly takes place after Sonic Adventure and S Hadow the Hedgehog, If you bother reading the text and codex. Also, didn't is seem like he used the emeralds to wake up Dark Gaia, who shattered the world, not the otehr way around.

The future Iblis destroyed still exists
In Sonic CD, you travel to the future, and either get a good or bad future. The bad future looks earily similar to the future Iblis destroyed. The Tiny Planet is probably caught in the paradox created in Sonic 06, since time is different on Tiny Planet. Further more, in Sonic Rivals 2, another dimension is revealed that looks exactly like the future Iblis destroyed. Its a city destroyed by fire, and there's a fire demonic thingy there named Ifrit. This "alternate dimension" is the future that was erased with Sonic 06, except it wasn't really erased and still exsists in some form.

Blaze's alternate universe is also a future to the current timeline
Maybe the universe is parallel but also the future. It would explain how Rush Blaze and St H 06 Blaze are the same, which they are clearly intended to be.

In the Archie comics Sonic the Hedgehog has part of lihikans life force
Hencefoth, the super transformations. also,he has Hydros's life force as well.

You're naked in Sonic's world if you're not wearing gloves
Everyone is wearing gloves, even Dr Eggman. Even if they aren't wearing anything else. One scene of Sonic X even shows Rouge bathing with her gloves on! Also, in Sonic Unleashed, when Sonic turns to the Werehog, his gloves get ripped off, but then they become Magic Pants as they reapear. The reason for this is the same reason the Hulk keeps his Magic Pants, you're naked on Sonic's world without gloves. Mobian Moral Guardians force everyone to wear gloves.
 * This is also the reason we don't see reproductive organs on any of the naked animals- said organs are found on forelimbs.
 * But that means... eeeeeeeeeewwwwwwwwwwwwwwwwwwww.
 * Hmm...Does that mean the mobians are the same species as Kif?
 * About the Sonic X bit: Wouldn't Rouge, of all people, at least take off her "clothes" to bathe? Or would we take this to mean that, in fact, by her world's standards, she's extremely prudish? (Only to accentuate what the humans sexualize instead? Hmm...) Finally... wait, when was this?
 * So does that mean everyone in Station Square in Sonic Adventure was naked?
 * While it's quite amusing to imagine Station Square as a giant nudist colony, it's more likely the gloves taboo only applies to animals, and the reason some humans adopt it is because it happens to be fashionable.
 * Robotnik probably hangs around furries more often than the people in Station Square and Capital City, so he knows taboos and customs of animals and wears gloves to prevent cultural shock.
 * Hang on, does this mean that Darkspine Sonic was fighting in the nude?! He's wasn't wearing gloves or shoes…
 * By human standards he was already fighting in the nude as Darkspine Sonic! How has it taken you only now to notice?

The Storybook Series presents a set of fantasies created by Sonic to deal with the psychological trauma of previous games.
Related to some of the above. Each storybook games takes a classic but somewhat varied story and disrupts its plot on a large, often metatextual, scale. The heroic story (Scherazade's and Aladdin's or Arthur's) is stopped by some kind of outside interference in the story, such as the intrusion of realism or broad concepts into Sonic's heroic adventure. Characters in the piece are replaced with the image of people Sonic knows where appropriate, except in the particular case of a constant feminine image never shown in the real series. In Sonic and the Secret Rings, this feminine image, personified as the genie of the ring,. This reflects Elise in Sonic 2006, who was. Sonic created the story of Erazor Djinn erasing the Arabian nights to stand for Solaris' threatening space-time, with Elise (as Shahra). Since Sonic, the story of Secret Rings, really a feverish hallucination, allows him to deal with what happened. He  in order to pretend that he had control when he. The other characters, represented as heroes within the different stories, are Sonic confirming what would have been lost to himself.

Since that bit of therapy worked so well, his mind rehashed the events of the Sonic Adventure 2 Cycle (Sonic Adventure 2, Sonic Heroes, Shadow the Hedgehog) and Sonic Unleashed in the same manner as an excuse to avoid a date with Amy--one to which Sonic apparently consented in the first place. Arthurian legend revolves around mortality, the quest for ultimate power and ultimate morality, and some gender issues, making it perfect for this task. The end of the Round Table in the normal story symbolizes normal mortality, normal life and death;  seeks to halt that cycle to preserve happiness eternally, but fails to see that it comes at the price of a deal with the figurative devil, specifically the underworld. This corresponds to Gerald Robotnik's dealings with GUN and  to preserve Maria's life indefinitely. Merlina (who sounds like Shahra, her counterpart, who was voiced by Maria's voice actor in the English dub) in some ways represents both Maria and and Eggman, caught up in the failings and image of a grandparent and desperately trying to right that wrong. In some ways  represents Shadow--an atrocity created for an ulterior motive who fails in his task, and is ultimately a cover for a greater villain--Black Doom or.

However, Sonic is only blending the familiar story of the Robotnik family shame with Arthurian legend to deal with his own negative feelings about the Dark Gaia incident. The Black Knight represents the werehog, or at least what Sonic was afraid the werehog might become, and Arthur represents Sonic. Sonic is clearly anxious about his werehog form through Unleashed, and his and Chip's revelations about its power imply that Sonic would have at least been tempted toward darkness, simply enabled to fight it by. The Black Knight represent what he feels the werehog truly is, that is,. Merlina and Caliburn both stand in for Eggman, with Merlina representing  and Caliburn representing Eggman's tendency to bring out the best in Sonic and enable him to fight the true ultimate foe (Chaos, Biolizard, Solaris, Dark Gaia). Amy's prominent and positive role as the Lady of the Lake is a result of Sonic's increased respect for her due to her. Her being  signifies a concern that Amy's trust in him is misplaced.

His ultimate transformation into  represents his ability to triumph over the evil inherent in the werehog form without abandoning the power it lends him; his defeat of the final boss signifies his intent to bring good and evil, life and death, and the very world back into balance. The reason time and mortality are such a focus in the game is that given the obvious pain of the werehog transformation and some Wii S 2 dialog about Sonic's appearance, is that Sonic must have believed that  and he was trying to prepare himself for his inevitable death, either from the events of Unleashed or a later incident.

Every single path of Shadow the Hedgehog actually did happen.
Shadow has entered an endless recursion of time which ends and recurs after he receives all seven Chaos Emeralds in each ending. The only way to stop the loop is to destroy both Black Doom and the Black Comet before the 'this is who I am' sequence occurs. Shadow may or may not be completely oblivious to it by the end of each story path, but he definitely has his memory wiped at the start. After the final ending, every single path of memory comes together, leaving Shadow dreadfully confused as to what his true purpose is. And so the game segues into the plot of Sonic Battle, where Shadow is still completely lost about where he's going, but at least has all his memories back.

Adventures of Sonic the Hedgehog is canon, and thus its charecters will appear in Sonic Colors

 * It is trying to be more lighthearted. Imagine Wes Weasley selling tickets for the park or Scratch Grounder and Coconuts as a sub boss.
 * If such were the case, then why did Shadow The Hedgehog lack Sonic the Hedgehog characters?
 * Or any Underground ones in 06?
 * Jossed. Scratch And Grounder have exipes though.

Adventures of Sonic the Hedgehog is canon, and Scratch and Grounder's AI were transferred into new robots.
Orbot and Cubot, to be specific.

Mobius is the Saiyan's original home planet thousands of years before the events of Dragonball and Sonic's Species are the ancestors of the Saiyans.
Before they evolved they could only go Super Saiyan by collecting the 7 Chaos Emeralds, but they evolved a way of going super saiyan without it, and the werehog transformation evolved into the Oozarus.
 * Does this mean that Sonic is the ancestor to the House of Vegeta?
 * I'd say Shadow is Vegeta's Ancestor and Sonic is Kakarot's

The Cosmic Interstate explains all the continuities.
Every continuity with Sonic, from SEGA to Sonic the Hedgehog to Adventures to Fleetway all exist as universes on the Cosmic Interstate. As for the differences of SEGA's Blaze and Archie's Blaze,they are two close timelines of one another.
 * Um, isn't this canon? Very earlier issues of the Archie comics show that alternate universes can be accessed by just cruising down the Cosmic Interstate. In the very first issue the Interstate is featured in Sonic makes contact with Anti-Mobius/Moebius for the time. Later issues show Sonic meeting a large variety of different versions of himself. He even makes contact with the Sonic Underground continuity and one that most people consider to be The Movie continuity. It's only logical to assume that all other Sonic continuities are accessible from the Interstate as well.

The SEGA continuity is the Cosmic Interstate's Earth Prime.
The Archie continuity has explored several universes, including other continuities. Yet we've never seen any cross-continuity crossover between the two. This is because SEGA continuity is the equivelant of Earth-Prime, and destroying it would destroy all Sonic-based realities.The reason the No Zone regards Archie continuity as the Prime Universe is due to the main continuity hiding itself from them.

The reason for the looped and/or suspended streets.
They built them that way. There's no way for a normal car to use them, so why do they exist? Well, it's a little like a lightning rod. Chaos Energy "likes" rings and loops and things of that nature; it's why there are rings hanging in the air, as well. The city tried building a normal city without them, but their normal roads quickly became warped and twisted. So, they built sections of useless (until the Sonic characters use them) roads so the Chaos Energy will maybe mess with them and leave their normal roads alone. They even put loops in spots so it'll flow better! Remember the loop on that building in Sonic Adventure 2? Do you think it was built just so Sonic can take it and run down the building? Or how about the first part of Speed Highway in Sonic Adventure? Lots of streets, but no cars; after all, who would drive on them?

Mobius is an alternate universe of Bleach

 * Just think about it. All of the characters in Mobius can be matched with characters from Bleach.
 * Silver= Toshiro Hitsugaya, Knuckles= Renji Abarai, Amy= Orihime Inoue, Sonic= Ichigo Kurosaki (duh), etc...

The Sonic series takes place in and around a fantastic version of New Zealand
Officially, the Sonic games take place on and around South Island, which is in the Pacific Ocean. Now, there's actually an island by that name in the Pacific Ocean, and it's part of New Zealand. Seems a logical enough conclusion.
 * And considering that New Zealand is considered to have the most bizarre geography in the world....

Sonic the Hedgehog and Animal Crossing are set in the same world.
Both feature humans living alongside large-headed anthropomorphic animals, with nobody considering this unusual. Sonic is a distant relative of the Able Sisters, but doesn't often visit because he interferes with people's fishing by running everywhere.
 * My extra theory: Animal Crossing takes place several thousands of years ago on a distant planet from Earth. Tom Nook is a Nocturnus. He pretty much destroyed the cilvilization seen in Animal Crossing with Dark Gaia. He managed to get to Earth and create Rouge, a bat-human hybrid, and stuffed her in a gyroid as a baby. He's now in the Master Emerald.

The various stories in Sonic Adventure are parallel universe versions of each other, albeit unusually closely connected in weird ways.

 * The evidence for parallel versions:
 * 1) The dialogue. Significantly different for just about every line witnessed by more than one character. Could be chalked up to the twice told tale effect, but there's better evidence to come.
 * 2) The tweaks to the level layout, such as: The positioning of the Chaos Emerald in Casinopolis. The positioning of the Capsule in Sky Deck. The handle or lack of one in the Hot Shelter room where Big finds Froggy. And so on.
 * The evidence for connections:
 * 1) Items. Any items a character collects in one story becomes visible in another, even if the character wouldn't be at that part yet. This is most easily seen with the Rhythm Badge and the Warrior Feather.
 * 2) Chao. Like with the items, the state of the Chao is chronological to the player, almost certainly not to the story.
 * 3) Emblems. Similar to the Chao, finding an item with one character makes it inaccessible to another character, even if, in-story, the collection would come after the other character's seeing the empty spot where it will... been.

Mighty is a backup Guardian.
That's why he wasn't in Heroes, and why Knuckles ws hanging out with Tails: it was his day off, so Mighty was filling in.

The heartbeat-like sound effect that plays whenever Sonic uses Time Break in Sonic and the Secret Rings is actually the sound of Sonic's heart beating.
Sonic utilises the flame arrow currently impaling his heart as well as Shahra's power in order to use Time Break and Speed Break right? So whenever the flame arrow's power is called upon in order to use Time Break, the organ it's currently impaling beats in response and becomes the only audible thing during Time Break.

Great Eastern Entertainment's next Sonic plush is...
Blaze.

Knuckles' story in S3&K happens after Sonic's, but with a twist.
Most people are already aware that when you play Knuckles mode in Sonic 3 & Knuckles, it chronologically happens after Sonic's finale following the Doomsday Zone during the timeline. Hence why the Death Egg doesn't appear in the background for the Lava Reef and Launch Base zones for Knuckles (it had already left), why the ghosts in the Sandopolis pyramid were already freed, why the Sky Sanctuary zone is considerable smaller for Knuckles when most of it was destroyed in Sonic's story, why Angel Island is airbourne at the start of Knuckles' story rather than on sea level like Sonics'. But then people find themselves confused when Knuckles' story's Angel Island magically survived the huge forest fire that Sonic's story endured, and why the same forest fire scenario is back.

Well, to remind everyone: if Sonic doesn't get all 7 super emeralds (i.e. 1 super emerald being the merger of 2 chaos emeralds, one from Mobius and one from the Floating Island, making 14 emeralds altogether adding both regions) but manages to reclaim at least 7 Mobius chaos emeralds back from when Knuckles first stole them in the intro, he'll still have access to the final Doomsday Zone (but only as Super Sonic rather than Hyper Sonic). But rather than the 'good' 100% ending, it will briefly show an Egg Robo at the end emerging from a pile of scrap metal. This is implied to be the same Egg Robo that serves as the 'antagonist' for Knuckles' story, in replacement of Robotnik. Sonic has his own intro at the start of S3&K, just like in Sonic 3, where he flies in on the island as Super Sonic before Knuckles steals his emeralds (same zone/story), but when you begin Knuckles' story in S3&K he just sorta... starts the level, with no implication of story or motive.

The confusion is, Knuckles has his own intro for his story, but it only appears in Sonic & Knuckles alone and not when it's locked on with Sonic 3. those that played Sonic & Knuckles alone, who started Knuckles' story, would remember Knuckles being startled by the Egg Robo dropping a bomb in Mushroom Hill (first level of Sonic & Knuckles), in which Knuckles claims revenge and consequently starting his 'story mode' at Mushroom Hill. But those that played through Knuckles story locked on with Sonic 3 (thus playing Sonic 3 & Knuckles, where the Mushroom Hill of S&K was actually the SEVENTH level of S3&K due to being placed after the six levels of Sonic 3) were not treated to this S&K intro. Thus if they were not aware of the intro in Sonic & Knuckles alone, they were often left confused as to why Knuckles was chasing and battling this random Egg Robo instead of Robotnik. When they get to S&K's first level of Mushroom Hill in S3&K (the seventh zone with the two games combined), this intro is still absent and just treated as 'another Sonic 3' level.

Basically, the Sonic 3 levels in Knuckles' story never happened for Knuckles during his story mode. They were just there to show you could use Knuckles in the Sonic 3 levels (the same way he can play in the Sonic 2 levels with lock on technology, despite not being present for that story), and a mild representation of the routes Knuckles took as an enemy in Sonic's mode. The new 'Knuckles' paths in the Sonic 3 zones (featuring the new boss locations) are there to show you just HOW Knuckles was able to get through the level quicker than Sonic through shortcuts (after all, he is the guardian of the island, so he knows alternative routes) thus always ahead of Sonic to taunt him when he catches up. The airbourne Angel Island backdrop, and the absence of the Death Egg sprite in Launch Base are mearly evidence and clues to help you realize Knuckles' story happens after Sonics'.

Why would Knuckles have to travel through the Sonic 3 zones, i.e. half the island, to get to where he wants? He's the guardian of the whole freakin island, he's spent his entire life there, he knows every route inside out. Sonic needed to explore the island from the coast to find the Death Egg, Knuckles just needed to go straight to his destination. Granded it involved him using the Flying Battery as a shortcut to get to the Sandopolis desert, where he knew the Lava Reef zone's Hidden Palace was hidden in the Sandopolis pyramid. But why would he bother going through the Hydrocity, Marble Garden, Carnival Night, Ice Cap AND Launch Base if he didn't need to? In regards to the emeralds, if it's implied the Egg Robo that replaces Robotnik in Knuckles' story is the one from Sonic's neutral ending where he only gets 7/14 chaos emeralds (the Mobius ones that Knuckles originally stole from him), then it's up to Knuckles to get the remaining 7 emeralds that he knows were on the Floating Island anyway, consequently acquiring all 14 emeralds and activating the super emeralds. Because when playing Sonic & Knuckles alone (without the Sonic 3 lock on) there is no 'super emerald' feature, and the special stages play out as if you were just collecting chaos emeralds in the normal Sonic 3 fashion, but from S3&K they become super emeralds in Knuckles' story because it's implied Sonic already got the Mobius emeralds back and likely kept them in the Hidden Palace's emerald chamber. This of course means Hyper Sonic isn't canon, but then had you 'seen' Hyper Sonic in any other game? This helps to explain how weird unnatural stuff happens for Knuckles in Sonic 3 levels that had already happened to Sonic, unless the Egg Robo just wanted to troll Knuckles with deja vu for a laugh, like the forest fire in Angel Island being magically healed up, and then starting again.

Knuckles' intro starts at Mushroom Hill (the seventh zone of S3&K), thus Knuckles' mode starts at the seventh zone, as it is the first in Sonic & Knuckles alone.

Sonic the Hedgehog 4: Episode Metal is a prequel to Episode 2.
After Dr. Eggman revived Metal Sonic, the latter is sent to train in Splash Hill et al., essentially experiencing Sonic's latest adventure in order to be brought up to speed and prepare for the rematch against Sonic.

Sonic Generations will be a downloadable title

 * Jossed, it's a physical product.
 * Well, the PC version is downloadable through Steam at any rate.

Silver won't return in Mario And Sonic London 2012
It says that there are 20 playable charcters.
 * Jossed. But it was'nt clear if he was playable or not, he could just be a Rival/Boss.

The next Sonic Storybook game will be about Grimm's Fairytales.
And in this game, Sonic will play the part of Hans the Hedgehog and be able to ride a giant rooster, Yoshi-style. Hansel and Gretel will be played by Tails and Cream, Little Red Riding Hood will be Amy Rose (With Shadow being the Big Bad Wolf; come on, any excuse to get Sonic and Shadow to fight again!), and Blaze the Cat as Snow White. Heck, the whole story might even revolve around Sonic trying to find Prince Charming so that he can reawaken Sleeping Beauty in order to battle the evil witch who cast the spell on her. And Rumpelstiltskin would be the Witch's Dragon!
 * If Blaze is Snow White, wouldn't that make Sonic Prince Ferdinand, rather than Hans my Hedgehog?

Tails and Knuckles will eventually be playable characters in Sonic the Hedgehog 4, "eventually" being the key word.
This is why both of their names don't appear in the Project Needlemouse Character Countdown (See here for the original image). In Episode 1, Sonic will indeed be the only character available, but Tails will show up in Episode 2, and Episode 3 will get Knuckles involved. You see, the episodes are structured in a way similar to the original trilogy (the first had only Sonic, the second had Sonic & Tails, and the third had all three), and a system similar to Old Save Bonus will let you use Tails and Knuckles in the earlier episodes (not unlike Sonic & Knuckles's Lock-On Technology). In short, a clever way of using the Episodic Game format to introduce playable characters like in the original games.
 * Semi-confirmed by Word of God, but it looks like we're getting both in episode 2. Maybe. Of course whether both will be PLAYABLE on episode 2 is up for debate.
 * Alternatively: We get Tails in 2, Knuckles appears in 3-- possibly to throw a boulder at someone or punch them in the face-- and then joins up for real in episode 4... or whatever it would be called.

Espio the Chameleon will also find his way in somehow.
In Episode three.

Sonic 4 is dead

 * Jossed. It's said to be still in development.

If Shadow the Hedgehog does get a sequel...

 * It will take its Darker and Edgier tone to over-the-top levels and actually get the characters to say stronger swears like the f-bomb. And all this will be intentional (much like House of the Dead: OVERKILL), just to mock how Narmful the original game is and actually make it as funny as possible.

In a future installment, Mephiles will be the main villain.

 * It'll turn out that Generations somehow reestablished 06 as part of the main timeline (the reappearance of Crisis City seems to hint at that) and enabled Mephiles to return. Only this time, he won't be shackled down by a crappy Obvious Beta game and free to exercise his Magnificent Bastardry to his fullest extent.
 * Crisis City was in Sonic Generations. Maybe Mephiles will use this to escape into the main timeline.

Possiblities for the 25th anniversary celebration.

 * An actual crossover with Mario. I don't just mean another Olympics game, I mean an actual storyline event. It'll involve a rift in space-time, merging the two universes. Bowser and Eggman will team up to fight each other's enemies, and conquer the planet, and it's up to Sonic and Mario to save the day. Expect a representation of the Nintenod/Sega rivarly. The rift may be due to Dimention/Eggman Nega, who would serve as the Bigger Bad.
 * A crossover with the Alternate Continuity that the series has made. They'll be the Adventures, SEGA and the Archie continuities.

There will be a 3rd Sonic Adventure

 * It will have the original Sonic Adventure 1 and 2 cast playable, (sans Big the Cat, Gamma, and Eggman) and with each character having their own mini story like in 1.
 * Possibly Jossed by Sonic Unleashed a.k.a Sonic World Adventure.

Eggman will not be the villain in the next game

 * If you recall, at the end of Generations he was trapped in a time rift with his classic counterpart

The next Sonic Storybook game will be based on Moby Dick

 * Eggman will play the role of the titular great white whale, and his name will be Mobius Dick.

Shadow will get his own Storybook spinoff series

 * The stories that he finds himself in will be Darker and Edgier ones with more mature themes left in.

Sonic 4 Episode III will be set on the Little Planet.
Sonic will confront Eggman and the Death Egg mk. II directly, taking the battle there. The Past-Present-Future gimmick will be present, and Sonic will collect Time Stones in the Special Stages.

The next main title will contain other playable characters
SEGA now knows that they have a working formula. They're free to expand on it as they please, and done of the best ways is to add more characters. Not like Adventure or Adventure 2 or 06. They will be exactly the same as Sonic except with a special ability, just like Sonic 3 and Knuckles. In fact this will work even better now that we have the homing attack. Before Sonic was the weakest. He couldn't fly or glide or break boulders or climb walls. He was pretty much the standard character. However, now it can be said that the Homing Attack is Sonic's own special ability. It's still inferior to Tails' flying or Knuckles' gliding/climbing/breaking, but it does round them off a little more. Tails or Knuckles could also lack the boost.