The Elder Scrolls/WMG

The next game will take place in more than one province.
With PS 4 and the next Xbox on the way, there's nowhere for the Elder Scrolls to go but even bigger, and the only remaining areas in Tamriel are much smaller than Skyrim, Hammerfell, Morrowind, and Cyrodil. The only way to keep the series expanding and uphold its state-of-the-art reputation is to set the game in multiple areas, rather than forcing the customer settle for less.
 * Three problems: firstly, the main problem with increasing the size has nothing to do with the limitations of consoles and everything to do with the practicality of actually putting stuff in there (without resorting to heavy-duty random generation. Play Daggerfall - it is free nowadays - and see why that has its problems). Secondly, Bethesda doesn't need to make the game cover a larger portion of Tamriel to make the size of the ingame map larger - remember, Skyrim is a smaller province than Cyrodiil, but the game Skyrim has about as many square miles as the game Oblivion had: Bethesda can simply decrease the spatial compression (for another example, again Daggerfall shows up: the Iliac Bay area is actually a bit smaller than Vvardenfell, but Daggerfall was a huge game in terms of square miles, much, much larger than Morrowind). Thirdly, modern-day Argonia/Black Marsh is larger than modern-day Morrowind.
 * And that's not even getting into the idea that Bethesda could spend more focus on, y'know, a story. There is a limit to how far the idea of "new and advanced graphics" or "even more miles and miles of landscape", and (admittedly IMHO) Skyrim reached it. It's a beautiful game, it's got a metric buttload of quests, cities, and factions... what could be added by increasing the sizes?

Jauffre is the Eternal Champion.
He is about the correct age, and probably did a lot of cool things to get to his position.
 * Alternate theory: Jauffre is the Agent of the Emperor. He's a Breton, which would be the perfect race to send to Daggerfall. He's about the right age; the Agent should be about 58 at the time of Oblivion, while Jauffre is 60 according to the game files. After fulfilling his task for the emperor, Jauffre would have been readily accepted into the Blades, and probably would have easily climbed the ranks to Grandmaster, especially since the Blades' original task was to recover the parts of the Numidium, which the Agent did.

Centurion was a dwemer brand.
Most if not all dwemer constructs included in any game have the word "centurion" in their name: steam centurion, centurion spider, and so forth. This is very definitely a Non-Indicative Name since, well, centurions are officers (literally "leader of hundred men"), meaning one might as well name their robot army Sergeants. It does, however, make perfect sense as the name of a highly popular forging company, offering advanced constructs and other defense mechanisms to protect and serve dwemer and their interests around the world. You deserve only the best to secure your home and workplace from the inferior species: choose Centurion!

The Guards in Oblivion are telepathic Humunculi.
No matter where or when you commit a crime as long as there someone watching they come, even if horses are the only witnesses they come. They also seem to be able to communicate at distance and interrogate horses.
 * Horses do not summon guards, at least not after a patch.
 * Actually, the guards just have great vision. If you lower the guard vision variable, the victim needs to be near the guard at some point for them to give chase. They still chase you anywhere you go, however...

The Night Mother, Sithis, and Mephala are all the same being
not sure how to better explain this one but considering that Mephala is hardly consistant even in the matter of its gender and it enjoys messing with people why not for a little amusement cause a schism amongst its own people?
 * I think this is confirmed by the in-game book Fire and Darkness.
 * Proposed? Certainly. Confirmed? Not necessarily. Scholars squabbling over the reality of their own universe would be nothing new to The Elder Scrolls. Alternate theories on the Night Mother are proposed in the books The Brothers of Darkness and Sacred Witness. None of these books mention any connection between Sithis and the Night Mother/Mephala, however, and indeed, the Dark Brotherhood in Oblivion insists that Sithis is no Daedric being, does not reside in the realm of Oblivion, and they do not make even one mention of Mephala.

Between II and IV, some mage discovered how to use Restoration Magic to cure baldness.
This explains why the Emperor is bald in II, but has long flowing hair in IV. It also explains why there are no cut-balls in IV.
 * He had hair in I, lost it in II, then regrew it in IV. Weird...
 * I would theorize instead that each emperor is a different person. Arena Emperor is Uriel Septim VII, could Daggerfall Emperor not then be Uriel Septim VIII and Oblivion Emperor be Uriel Septim IX or even X?
 * Nope, in-game sources say it's the same emperor. It was mostly a different art team working on the respective games, so it may just be coincidence or simply the magic baldness cure.
 * Also, the guy standing next to the Emperor in Daggerfall's intro is Ocato, who, again, lacks hair in Daggerfall and has hair in Oblivion (he also, er, got pointy ears), so there is something this WMG, or it simply being a trend at the Imperial Court, would explain that 'different emperors' wouldn't.
 * I don't see why he couldn't have just shaved his head in II, got bored of that hairstyle, and let it grow out again...
 * That's not as fun.
 * No doubt, the real reason, is that Bethesda didn't want to make him bald on account of Patrick Stewart voicing him in IV. They may have felt it too obvious. Though there is a Patrick Stewart fan mod for the game, I hear.

The Imperial City Dungeons double as a homonculous-producing facility.
This explains why heroes often start off in prison with no backstory; they were created in prison. This also explains why there are no children in Cyrodiil; everyone is spawned in the Dungeons, fully-grown. It also explains why they can't take off their underwear, as they don't need to use their reproductive organs to reproduce (and note: in Daggerfall, you could strip totally naked, and male characters had no genitals.) And last but not least, it explains why soldiers and certain other types of people look identical to each other: those strains of homonculi are mass-produced.
 * Ooh! Ooh! And since everyone starts out in a dungeon, everyone is born flawed--ORIGINAL SIN! Original sin in Tamriel!

Dagon's promises are all empty, and everything he says is a lie.
Mehrunes Dagon's lovely promises of greatness and ascended mortality to those who follow him are all bunk. He doesn't mean any of it; that silly book he wrote is just his method of manipulating foolish mortals and tricking them into helping him take over and destroy the mortal realm. Had the heroes of Arena and Cyrodiil not stopped him before things could go that far, he would have betrayed his faithful mortal servants and slaughtered them too.
 * Is pretty obvious that he doesn't really give two craps about the Mythic Dawn and is just using them as worthless pawns, given the number of imprisoned (and dead) Mythic Dawn agents we see inside Oblivion gates.

Why Claudius Arcadia wanted Rufio dead.
If you talk to Rufio before you kill him, he refers to a women who he harmed in some way. Perhaps she was related to Claudius Arcadia, or was even his lover, and he wanted revenge.
 * Actually, I think Arcadia wanted him dead because he killed his daughter while trying to rape her.
 * Daughter? I guess that works too; I always thought it was his wife.

The Arch-Mage in Oblivion has a secret.
He's a vampire, a listener for the Dark Brotherhood, an escaped convict and the Grey Fox.
 * Not to mention

Who are you, at the end of Shivering Isles?
Gosh, I guess this just isn't Wild enough for Wild Mass Guessing... but, I'm gonna say it anyway: at the end of Shivering Isles, you  Like the final boss says,   Your powers are weak, sure, FOR NOW! But you still have the ability to  And, let's not forget that you are
 * So you're saying that you become a god at the end of shivering isles? Wasn't that stated outright?
 * Being, yes. This WMG appears to suggest that the Champion of Cyrodiil will grow increasingly fitted to the position, with the powers gained at the end of Shivering Isles being merely the start. That is not stated outright.
 * Confirmed. Sheogorath appears in Skyrim, looking and talking like Sheogorath from shivering isles, but mentions having been around for the whole Oblivion Crisis and drops a lot of seemingly random words that are associated with Oblivion quests.

Jyggalag was always the Prince of Madness

 * Where as Sheogorath is the manic-depressive form of madness, Jyggalag is the obsessive-compulsive form. Everything in its place, everything orderly, taken to its horrifying conclusion.
 * I Like this one.
 * And the cycle of Greymarch is not exactly because of a curse, but rather a cycle of Split Personality Takeover, and the PC was Sheogorath to begin with, thus in the end of SI the PC is simply reaffirming that identity, if we consider the implications of Jyggalag/PC as a case of Literal Split Personality and yet they are still both Daedric Princes themselves this might indicate that Jyggalag/Sheogorath was the strongest Daedric Prince, and this would justify the game-breaking exploits (which could possibly allow you to kill Mehrunes Dagon) as a manifestation of the PC's latent power as a fragment of the most powerful Daedric Prince.

The Mannimarco who appeared in Oblivion was an Impostor

 * Think about it, they spend all of this time building him up, terrible, terrible stuff, go over his LONG history of evilness and cruelty, then what do we get? A puny squishy wizard. Answer? It was never Mannimarco at all, simply a impostor trading on his name.
 * Another theory is that it was Mannimarco, without the "God of Worms" bits. That might not seem like much of an explanation for why this Mannimarco is much less of a figure than the King of Worms we met in Daggerfall... unless, of course, the removal of the God of Worms was done by simply removing everything that made Mannimarco the God of Worms, including the bits that was simply "of Worms". That reputation we've gotten to hear over the games? Mannimarco as the King of Worms. The Mannimarco we met in Oblivion? Simply Mannimarco laying claim to a title no longer truly his (said title being the King of Worms. He still can rightly call himself Mannimarco).
 * Maybe Mannimarco was split into two beings after the Warp in the West, leaving the mortal Mannimarco and the god Mannimarco both as legitimate as the other. Considering he did mess around with the fundamentals of the universe it wouldn't be surprising.
 * Or maybe he remade his old body and used it was a decoy.

The Falmer will play some kind of role, in absentia or not, in Skyrim.

 * The Falmer being, for those less versed in the lore, the Snow Elves--the original Elven strain that inhabited Skyrim. As far as anybody knows, they're all gone, much like the Dwemer. But it's possible some parts of Skyrim might reference them or even make them a major plot point.
 * Confirmed to an extent. They're there and are fought in some rescue missions done for the Companions, but are essentially the Skyrim version of Goblins from Cyrodil. Its noted in some of the in game books that after they're defeat by the nords they fled underground, seeking refuge with the Dwemer, who blinded and enslaved them. They eventually devolved and once the Dwemer disappeared took over the empty dwarf city. The same book mentions that sightings of them have become far more frequent of late and hopes they aren't preparing to invade, so maybe they'll be given a bigger focus in DLC.

The guards in Daggerfall are artificially produced homunculi made from the same person

 * They are produced in a big number, and only a few roam around the town. When a crime is committed, they show up and start spouting "HALT!", the one line of vocabulary they know.

The Dragon that you can summon towards the end of Skyrim will be from Oblivion

 * The makers of the game have already clearly stated that you will be able to summon a 'named' dragon towards the end of Skyrim. Who better to help you combat the evil dragons in Skyrim sent by who is essentially Akatosh's evil sibling than

The Elder Scrolls VI will feature the hero saving the whole of Tamriel from the Thalmor

 * The High Elves have gone full Nazi, having conquered the wood elves and khajiit and already fought the Empire to a draw once. If canonically, the Empire loses in Skyrim and  the whole continent could easily fall under their sway. Elder Scrolls VI will start with you as a political prisoner about to be executed by the Thalmor, only for your execution to be interrupted by either:
 * A. Azura: showed up to help the Nerevarine, so there's precedence.
 * B. Talos: has also showed up twice to give the hero help and advice and as founder of the Empire would be against elves enslaving everyone.
 * The Thalmor also has a goal to remove Talos from existence (thus, the whole 'ban Talos-worship' thing they have in Skyrim). Talos presumably would prefer to still exist, especially as he is a god of Men, and quite possibly one thing keeping mankind existing.
 * C. A returned Nevarine and Vivec who have returned from Akavir to find the Empire in ruins and Morrowind destroyed. However, Vivec's godly power is all but gone and the Nevarine's supposedly cured Corpus has gone terminal and they have singled you out to do the work for them. The Nevarine will be too deformed to be recognizable as anyone race or gender (solving the customization problems)and will only have enough strength to point you in the right direction.
 * E. Sheogorath: Who  rescues you and acts as the most hilarious schizophrenic mission control ever, giving frequent and hilariously wrong recollections of his own actions in IV along the way.
 * F. The Last Blade: boring but most likely.
 * G. Liberty Prime: Because... why not?
 * H. A mysterious stranger who, later on, will be revealed to be
 * I. The Psijic Order. Taking a similar role to the Blades in Oblivion, they will act as your support faction. The Psijics have a history of conflict with the Thalmor, are primarily made up of high elves, thus showing not all are bad in a major way, and the College of Winterhold questline certainly sets up some plot threads to be tied up later that could easily tie into the main fight with the Thalmor.
 * And
 * J. The Dragonborn. He's back, and he's ready to destroy the Thalmor once and for all, either because he wants to get rid of the Empire's allies (if he's a Stormcloak) or because he wants to save the Empire from their control (if he's a Legionnaire). Of courrse, this would never happen due to having to establish a single canonical version of a past hero, but it would be awesome.
 * Moreover, the lands under Thalmor occupation (at the time of Skyrim) are Elsweyr, Valenwood and the Summerset Isles, all places that have yet to be the focus of an Elder Scrolls game.
 * Also, Elsweyr and Valenwood put together are only about the size of Skyrim and smaller than Cyrodiil. Using both(or all three) in one game would provide for a great deal more variety in environments than either Oblivion or Skyrim while still keeping the same basic size of the game world.

The Champion of Cyrodil was supposed to be Emperor

 * He/She was clearly in the position to become the next Emperor and restore peace and order to the continent. However, becoming  robbed him of his sanity and soon the ability to manifest in the mortal realm at all. Thus, Chaos.

The Deadric realms of Oblvion are connected via a World Tree scenario.
There is some large interdimensional organism-like thing which every one of the realms of Ovlivion are anchored to. It is this "tree" that holds the realms together and it's magic is what allows the Deadra to remain immortal. The Aedra made great sacrifice to create Nirn, however the Deadra are still dependant on this "tree," though they may not know it. If any realm were to be cut off from it in some manner both it and any that reside in it would cease to exist, swallowed up by Sithis.


 * Well in the Shivering Isles Sheogorath's servants, the Mazken and the Aureals, mention going to "the dark waters of Oblivion" when they 'die' and must travel back to the Shivering Isles . Maybe those 'waters' are what separates/connects each Prince's realm and, like the World Tree, these waters all stem from the same source and are what sustains each plain.

Unrelenting Force will return in Elder Scrolls VI as a Greater Power for the Nords.
Because knocking guards around with nothing but your voice is just too awesome/hilarious to keep to just one game.

Climbing will return in a later game as an Argonian ability.
Because lizard ninjas.

M'aiq the Liar is a powerful Daedric prince with Dungeon Master qualities and is manipulating the events of at least the last 3 games.
Like he says in Oblivion, he knows much and tells some. The point is, his knowledge goes much deeper than even the most wise scholar could dream of. Its so deep, that when he tells something, this knowledge changes the world enormously.

For example, during Oblivion, he told the player that throwing weapons is foolish, because when holding your weapon you only need one. This causes the entire continent of Tamriel to forget how to make throwing weapons. He also told Levitation is for fools...and the levitation act is signed, outlawing it. And cryptically makes clear the player will see a dragon, resulting in the main quest ending.

In Skyrim he even starts to get freakier. He appears at the most random locations, as if he is observing you from a distance. He calls mudcrabs 'horrible creatures' turning them into threats to low-level players. Then he decides to practically doom Tamriel by saying dragons were never gone, only invisible, which causes Alduin and his lackeys to go on a rampage. One can only hope he will not utter knowledge about the end of the world...

There will be a Skyrim expansion set in Morrowind
The events of the Infernal City novels basically trash Morrowind as a whole plot point. Red Mountain erupts, Argonians invade, and the Dunmer are forced to evacuate pretty much the entire province. Starting a Dunmer character in Skyrim prompts Hadvar to wonder if you are "another refugee", presumably from said events. The current state of Morrowind can easily be written into the backstory of an expansion. The Nerevarine could even make an appearance, being made immortal during TES III.
 * The specific area of Morrowind featured may be Solstheim, which we know was officially ceded by Skyrim to the Dunmer as a refuge. After all, the enviroment and many of the creatures are already in Skyrim, so that saves time and space, Solstheim is an island, so the need for artificial borders are decreased, and finally, we know the Bloodmoon is at hand again... as for the Nerevarine showing up, however, they'll almost certainly avoid that - they sent him or her to Akavir for a reason, namely to avoid having to give any details that could contradict a play-through.
 * The bulk of Morrowind is already in the game. Mostly untextured, completely unpopulated, and impossible to get to without exploits, but it's there.

The Champion Of Cyrodiil was driven crazy by watching the world fall apart
Not getting into why the new Sheogorath looks like the old one, one could imagine that the hero, now immortal and an eternal witness to the fate of the world, had to watch as the Empire fell apart, the provinces break apart, Morrowind suffer near destruction, their own efforts practically spat on by a group taking credit, and in general... everything they fought so hard for crumbling away into nothing despite their best efforts. The new Sheogorath isn't crazy and jaded because of some inherited madness, but because of the stress of it all. At least in the Shivering Isles, things are more constant and he/she is better in control of everything.

There will be a Skyrim expansion set in Bruma.
Bruma, as seen in Oblivion, is culturally and environmentally similar to Skyrim, with a healthy Nord population. As such, it's possible that the Stormcloaks would want to capture the county and annex it into a hold of Skyrim. Or more likely, this would be a DLC quest, since it probably isn't big enough to warrant an entire expansion pack.
 * I'd think it being culturally and environmentally similar to Skyrim is a pretty good reason not to include it. If there was one complaint about Skyrim's environment it was that it didn't have enough diversity. Personally I think the complaint is baseless, but focusing on an area that we've seen to be snowy and mountainous isn't going to help that case.

M'aiq the Liar is a Time Lord.
In Oblivion, M'aiq says he's seen dragons, but he won't say where. He already experienced the events in Skyrim, then used his Type 70 TARDIS to travel back to the Oblivion Crisis.

The Player Character is the reincarnation of the same person in all the Elder Scrolls Games.
In Morrowind, we are told that the 'Player Character' is a reincarnation of a Chimer (Dark Elf) Lord named Nerevar. This wasn't the only incarnation for this character. The Prisoner at the start of Oblivion is another reincarnation. The Prisoner at the start of Skyrim is another. The prisoner at the beginning of Daggerfall was a past one. Its the same guy/gal coming back time and time again like a cosmic trouble shooter. This makes Nerevar truly a Hero of Another Story from a "lost" Elder Scrolls Game that never got made (with the first battle against Dagoth Ur being the final boss battle).
 * Can this be reconciled with the Champion of Cyrodil's ascension to Sheogorath?
 * His/Her soul was split in two?
 * While you can choose to RP your Skyrim character as your Oblivion/Morrowind character, it won't work for the Oblivion prisoner to be the reincarnated Morrowind prisoner, because Oblivion takes place six years after the events of Morrowind.

The Elder Scrolls 'Verse is literally an RPG 'Verse
This is a little hard to phrase, but bear with me. The Elder Scrolls universe in reality was adapted from the creators' D&D campaign. But the series does not take place in its own "Universe", but rather we are seeing what life would be like for actual characters in an actual RPG universe. First, the PC literally does not exist until you create him/her at the start of a new game. No history, no family, no friends, no background whatsoever other than "race" and "class". Second, the Multiple Choice Past of the world's history means that history is flexible. Only possible with a GM-induced Retcon. Finally, and most important: The Elder Scrolls themselves. Even Paarthunax can't easily explain what they are, only that they are "fragments of creation" and "come from outside time". They can't be comprehended by the people living there. What are they? They are the GM's notes.
 * You lost me.

Dwemer Metal is actually Conundrum mixed in with something else
The "Secret recipe" used in making Dwemer metal has been lost in time, as well as the Dwemer. In Skyrim, underneath certain Dwemer ruins is "Blackreach", where Geode veins can be found. This COULD be their source of metal! You can only find Conundrum, Gems and Soul gems (which they could of used to power their machines). Conundrum and Dwemer metal are also a similar colour to each other.

If "Elder Scrolls VI" is kept to one province, it will be the Summerset Isles
War with the Dominion is all but a foregone conclusion by now (expect a Yol Toor Shul-sized Internet Backdraft if it isn't). The only question is whether the war will be Skyrim DLC or (as guessed above) the next game itself. Either way, Men weren't allowed on the Isles even when the Altmer were good guys, so a war/post-war occupation would be a perfect chance for Bethesda to have a game in that province and still have Men as PC's.
 * Besides, judging from the map, the Summerset Isles are in the tropics, i.e. a change of scenery from Bitter Up North Skyrim

Martin becoming the Avatar of Akatosh was the equivalent of The Second Coming for the people of the empire.
Notice how in Oblivion alot of people had lost faith in the Aedra and gone to the Daedra. No one is like that by Skyrim, so Akatosh actually coming down managed to convince many people to stay faithful.

Vivec's first mom is also a robot/cyborg
Vivec's first mom is possibly built by Sotha Sil or otherwise master-crafted to be able to carry Egg!Vivec inside. She also stays intact despite all the Dwemer efforts to get Egg!Vivec out of her. The prayer that Vivec gives her is probably some kind of shutdown signal, as he figures out that if the Dwemer don't remove him then he is gonna be stuck there forever.

The Dwemer, being who they are, are so fascinated by this Robot Girl / cyborg that they try to duplicate her, although their simulacrum doesn't work as well and therefore breaks down.

It's possible that the eighth monster-child, GULGA MOR JIL, is likewise related to Vivec's first mother. It has the exact same shutdown signal.