God's Hands Are Tied

There's a nasty enemy out there, possibly an Eldritch Abomination, God of Evil, or just a very powerful Evil Overlord. Even the gods are helpless before it, or so it seems. In fact, it turns out that while the gods are vulnerable to this enemy, a mortal is less so, so it's up to a mortal (i.e. Our Hero) to save the day. When this trope is in effect, there will be no Bolt of Divine Retribution and the most support The Hero can expect to get is a Holy Hand Grenade.

A variation on this is that the gods are bound by certain rules that an everydude is not (such as a Balance of Good and Evil).

If no satisfactory explanation is offered, then The Gods Must Be Lazy.

Compare Neglectful Precursors, Did You Just Punch Out Cthulhu?, and All Powerful Bystander.

Anime and Manga

 * While never addressed directly, this is the basic premise behind Kannazuki no Miko (behind the Schoolgirl Lesbians Humongous Mecha plot) and the title itself refers to the month of October, when the Gods were said to be away, hence Orochi was able to come back unopposed except by the titular Miko.
 * If a Death Note shinigami (god of death) uses his powers to kill a human in order to save another out of love, they will die. They're safe, though, if they don't care about the one they save.
 * of Higurashi no Naku Koro ni says this frequently to Rika.
 * Dragon Ball's gods seem to be bound quite a bit by this. This trope might explain why, during the Buu saga when the aforementioned Buu is devouring planets and even deities left and right that the gods don't extend Goku's one day on Earth indefinitely to give him more of a chance to fight.
 * The protagonist of Edens Bowy is a "God Hunter" who have the power to slay the immortals and is highly resistant to their divine magic. Against human opponents, however, this power doesn't do anything.

Comic Books

 * In The Sandman, Dream explains that, as an Anthropomorphic Personification, the same laws of nature which empower him, also bind him. This provides a reasonable justification for why he doesn't solve every plot point with the massive application of cosmic powers, without simply making him real dumb.

Films

 * Dogma to an extent. God could stop the threat but is indisposed, having assumed a vulnerable human form . The angels are unable to directly do anything on their own, so it falls to the last scion to save the world and rescue God.
 * The Backstory of Disney's The Black Cauldron involves a "a king so evil and so cruel, even the gods feared him".
 * Another one from Disney, and an odd variant of the Trope. In Tron: Legacy, Flynn practically is considered a god on the system he created...but his fallen-from-grace creation managed to out-fox him, making him a prisoner in his own creation. It would also be impossible to kill one without killing the other.

Literature

 * Everworld: Ka Anor can eat gods, but is dependent on his Hetwan hordes to handle their mortal supporters. The Queen of the Fairies even mocks the Hetwans for bringing up Ka Anor as a threat, which seems kind of badass when we see super-powered deities wring their hands over him.
 * Likewise, the Greek gods have a habit of giving mortal heroes their divine favors but not actually doing much fighting themselves---Ares and Heracles seem to be the main exceptions, but even they're prone to refuse for childish reasons. Athena, being more Genre Savvy than the rest, tries to convince them to get out and actually fight the god-killing abomination out to destroy them.
 * This is a basic premise of Lois McMaster Bujold's Chalion novels.
 * The Lord of the Rings is a major offender. The good gods of Middle-Earth live in the continent where Tolkien puts you when he doesn't want you to be a major part of the story anymore. In order to help the Free Peoples defeat the Big Bad, they send a grand total of five wizards. Only one of them actually does help, and the most powerful one turns evil. Wow, thanks for the help!
 * There was a halfway good reason for this; the Valar had come to help Middle-Earth a few times in person, or at least with massive armies, and every time the world went into the brink of destruction as a result. Possibly they feared that another armed intervention could cause more harm than good.
 * Just the army of Maiar blew up the sub-continent Beleriand, and if it hadn't already been depopulated by Morgoth's armies, all the Elves, Humans, and Dwarves there would have died. If the Valar themselves joined a fight, more than just a continent would be destroyed. That doesn't always explain why they don't take less physical involvement, although Ulmo does exactly that. At one point, Tolkien described Illuvatar (God) chiding the chief Vala for founding Valinor instead of staying in Middle-Earth to help directly.
 * Two of the five (Alatar and Pallando) went far into the East where the main characters of Tolkien's legendarium never go as "missionaries into occupied lands." Tolkien at first wrote that they indeed fell into evil, but later on he decided that they may have been just as successful as Gandalf, weakening Sauron's support in those lands and delaying military forces from helping him. We just never get the chance to meet them and find out.
 * A very late change in the story. For the vast majority of the history of Middle Earth, Gandalf was the only faithful wizard. Radgast withdrew to himself and lived with the animals instead of helping the fight, Saruman fell from grace, and the until recently unnamed blue wizards were never mentioned after they stepped off the boat.
 * In the Discworld book Hogfather, Death cannot . His granddaughter, Susan, on the other hand...
 * Also, although Death can remember the future, he's constrained not to take action based solely upon these memories. In Soul Music, he has to be told what Susan is up to by Albert before he can go to assist her, rather than simply pre-remembering where she's going to be.
 * The Auditors are also limited in their actions, being compelled to obey instructions, and being constrained from taking direct action in the world (unless they're sneaky about it).
 * The actual gods of Discworld are somewhat constrained by the rules of the dice-games they play, using mortals as playing pieces. Unless they're cheating, of course. Or misremember the rules. Or they mislaid some of the pieces. Or they're too busy laying bets on what's going to happen without their help. Mostly, they're constrained because they're just not all that bright.
 * Bridge of Birds is a case where the gods are restrained by rules--if they abuse their power, they can be deposed and replaced. However, they can help indirectly (leading to more than one half-literal Deus Ex Machina.)
 * In Tamora Pierce's Immortals quartet, a goddess is described as relatively minor everywhere else, but in one particular country 'all but the Black God must bow to her, and she is the Black God's daughter.' Guess who the heroine gets into hot water with!
 * Happens again in Trickster's Choice and Trickster's Queen: the god in question used to be a major power (and still is - in his home country) but then his people got conquered, which changed the power dynamics. He's not happy about this and has been plotting ever since it happened (two or three centuries ago) to fix it.
 * It happened in the final book of the first Tortall quartet! The heroine is told by the Great Mother Goddess that there are times when only a human can cause an outcome. Actually, this basically happens at some point in every Tortall series. (Not yet in the Beka Cooper books, but there's still another book to go.)
 * Happens regularly in Percy Jackson and The Olympians, where gods have ancient binding conracts restraining their behavior, but a hero can "go anywhere and challenge anyone" as long as he had the balls.
 * In King Rat, neither King Rat nor his fellow animal-kings can fight the Pied Piper, because they're too scared they'll be the one he'll use his music to control. Only Saul, who is half human and half rat-spirit, can oppose the Piper, as his hybrid makeup can resist both rat-control tunes and human-control tunes.
 * Not so much gods as Sufficiently Advanced Aliens, the Ellimist and Crayak in Animorphs can not directly (or at least, overtly) interfere with other species under normal circumstances, generally guiding their allies or followers instead. The reason is that these two beings are basically locked in a galaxy-wide Cold War: the Ellimist is good and wants to help everyone, Crayak is evil and wants to destroy everyone, and any open conflict between them would probably be very, very bad for everyone involved.
 * The Ellimist Chronicles shows what happens when their hands are not tied. If I remember correctly at least 10% of the galaxy was destroyed before the Ellimist acquired his interdimensional powers. The Cold War style battle is required to keep the fabric of reality from falling apart.
 * In David Weber's Oath of Swords, Bahzell takes the War God to task for his failure to prevent the disaster that shook up the world and decimated Bahzell's people. Tomanak goes on for pages outlining a scenario where the Light and Dark gods are at constant war all over the universe, and cannot meet directly in any given encounter for fear that the overflow of power would grind the world to dust.
 * He also notes that the good gods spend a lot of their effort stopping the really powerful demons from entering into the world. Considering that the weaker demons that can get in are a pretty serious threat even to a champion this is probably a very good thing.
 * The Arcia Chronicles are set in Tarra, a world created by the so-called Old Gods. Said Old Gods were then rendered Deader Than Dead by the invading "Lightbringers", seven extradimensional gods serving an overdeity they call "the Light". Seven thousand years later, though, the Light calls all of them back to Its throne, because new dangers to It arise. So, Tarra is left unprotected against lurking Cosmic Horrors and it's up to the local mages to fend them off like no tomorrow.
 * In the Belgariad by David Eddings the gods have absented themselves from the world because if they get to fighting with their evil brother Torak again, they would likely destroy the world. Also, everything--even the gods--is being controlled by two "Prophecies"--which are self-aware and more like super-gods than the conventional meaning of the term--but the two competing Dark and Light Prophecies fight for control of the Universe according to certain agreed upon rules, including acting through the agencies of a "Child of Light" and a "Child of Dark" (persons or even gods who exist in the world and can take action in it).
 * In The Screwtape Letters by CS Lewis, Screwtape explains that neither Heaven nor Hell works at all openly, at least nowadays, because Heaven wants people to pursue goodness without coercion or bribery, and Hell doesn't want people to realize there IS a Hell, because then the vast majority of them will realize there's a Heaven too and that will just encourage religious belief.
 * And in That Hideous Strength by CS Lewis, the angels and demons stay under cover basically to avoid escalating their conflict into a premature Armageddon.
 * Chronicles of Thomas Covenant: The Creator is of equal (possibly greater) power to the Big Bad, Lord Foul. But he exists outside of this creation, The Land. If he tried to enter The Land to deal with Foul directly, he would end up breaking the Arc of Time, destroying The Land. Which is exactly what Foul wants. So The Creator is forced to use proxies like Covenant.
 * The Gods rarely intervene directly in the Riftwar Cycle. This is explained partially by the Gods being bound by rules. As a result of this, the God that most frequently interacts directly with the world is Banath, God of Thieves, who is able to do so because breaking the rules is a key part of his nature.
 * In Dragonlance, whenever the evil goddess Takhisis comes to Krynn, she always has a mighty army at her disposal, including evil dragons and flying fortresses. All her good counterpart Paladin does to stave of total destruction is to come to Krynn as a bumbling old wizard who pulls a few strings here and there, which for some reason is always enough for the heroes to defeat the Queen of Darkness in the end.

Live Action TV

 * Stargate SG-1 is a prime example of this trope in the last 2 seasons. Turns out that there is an evil counterpart of their race that is just as strong as they are. Neither of them can destroy each other, so it is by all logic up to the simple human to defeat an army of godlike-powerful beings. Oh and it's also against their rules to help them, even if their own life depends on it! Otherwise they are Neglectful Precursors of the worst kind.
 * Thank you for being clear about it, but yes, this is correct. The Ancients, Ascended Being, take their Prime Directive quite seriously, and wouldn't intervene in the affairs of mere mortals, even if it meant that all life in the galaxy was wiped out. Worse, they refuse to even turn a blind eye; anybody who tries to help out lower beings is immediately demoted to a mortal. Most notably, they refused to do anything about the half-Ascended Big Bad Anubis, even when he threatened to wipe out all life in the galaxy, and stopped Daniel Jackson from doing anything about it.
 * It gets better, though: the only circumstances where the Ancients have broken their own rules is when their own butts were on the line. Merlin demoted himself to human and began to build a device capable of destroying ascended beings. This is perfectly within the rules as we know them. This prompted the Ancients to interfere and send one of their own, Morgan la Fey, to stop him. Hypocrisy much?
 * Not trying to excuse the Ancients' douchery, but Merlin did technically break the rules. When he retook human form, he retained all the knowledge he had gained when he ascended, which is the big no-no of becoming mortal again.
 * While the Ancients were definitely Neglectful Precursors overall, the Anubis situation wasn't the horrible neglect it looks like at first glance. The seemingly intractable problem - a disembodied Goa'uld with all the scientific knowledge of the Ancients - was finally solved by Oma Desala moving directly to fight him, meaning that she would be bound fighting him forever. It started with Oma Desala breaking the rules to help lesser beings ascend, only to be tricked into helping Anubis (which is the kind of thing the Ancients were explicitly trying to avoid by not interfering). As punishment for Oma, the Ancients half-way de-ascended Anubis, kicking him out of their club-house but leaving him with all their secret knowledge and access to all their old toys, thus creating the nearly unstoppable threat in the first place while laying all the blame on Oma. Sounds horrible, but remember, she helped him ascend in the first place. All the ancients were demanding was that she clean up her own mess by facing the consequences for breaking their only rule. Then again, they also leave her to figure out this solution on her own, not once suggesting that her sacrifice might solve the problem.
 * Except that they were basically allowing Anubis to kill people in order to guilt trip Oma into sacrificing herself, which is definitely douchebag behavior.
 * On the other side, we have the Ori, the Evil Goatee-wearing twins of the Ancients, who not only interfere in the affairs of mortals, but direct them to worship the Ori and kill or convert unbelievers. They have no problems with throwing their power around, and will grant their preachers some measure of their power. When they come after our galaxy, which had, until now, been shielded by the Ancients, the Ancients still refuse to do anything about the Ori, even when they try to destroy the Ancients. Buncha lazy ascended bastards.
 * Daniel says at one point that Adria claimed that even if the Ori could get the entire Milky Way to worship them, an outright fight between them and the Ancients would result in significant casualties for the Ori. It's possible that the Ancients believe that if it came to a direct battle between them and the empowered Ori, that they could have a chance of actually winning. It's also possible that "death" for a being at that level of existence means something different than it does for a mortal.
 * In Babylon 5, the Vorlons and Shadows (actually Sufficiently Advanced Aliens) seem to have a pact to manipulate the younger races without going directly to war against one another (though killing members of younger races seems to be fair game). When Kosh violates this by

Music

 * A major plot point in Richard Wagner's Ring cycle is Wotan being constrained by his own treaties.

Mythology and Religion

 * One possible answer to the ancient question why God allows evil to exist, even though he would have the power to stop it. Even if he wanted to, it could interfer with a greater plan beyond the scope of a human life time.
 * In the Hindu epic Ramayana, the demon king Ravana was blessed by Brahma to not be killed by any god, spirit, or other supernatural being. Vishnu exploited Ravana's only weakness - he became human, exempt from Brahma's ban. This makes this trope Older Than Feudalism.
 * In the mythos, Brahma is actually the source of a lot of the screwups that Vishnu (or, occasionally, Shiva) have to go in and fix. There is even a separate myth dedicated to explaining why he's The Scrappy of the religion.
 * Occurs in Greek Mythology when the Giants attack Mount Olympus. Most of the Giants have immortality clauses which state that no god can kill them, so the Olympian gods rely on Heracles to fight the Giants (or at least finish them off after the gods have beaten them up).
 * The Koran accuses the contemporary Jews of the area of using this trope, and it even uses the expression word for word.

Tabletop Games

 * In Exalted, when the Primordials created the world, they created the Gods to maintain it, so that the creators could enjoy playing Games of Divinity. The Gods resented their position as slaves, but were created so that they could not strike at their creators. So they gave powers to humanity and raised a number of Exalted to do the dirty work for them. The Primordials didn't see that coming...
 * The Primordials made everything with build-in restrictions so it couldn't harm them. Except for humans who were deemed too unimportant to bother. Exalted prehistory is similar to Ancient Greek creation-myths.
 * On a sillier note, the major gods in Exalted (the equivalent of the Olympians) don't interfere in Creation much anymore because they're all distracted by the Games of Divinity. These games are so addicting that not even gods can keep their attention away from them. Fanon consensus settled on calling them Ever Quest.
 * The gods in certain Dungeons and Dragons settings, most notably the World of Greyhawk, must abide by specific limits, such as not being able to manifest avatars or otherwise interfere directly in mortal affairs. Mostly, this is a way to Hand Wave the question as to why the gods don't simply manifest and solve certain problems themselves, forcing mortals (such as the Player Characters to do the dirty work. That said, in some cases the gods can act directly if their human agents fulfill certain quests-in Greyhawk's case, the goodly god Rao was able to actively banish all the demons still loose in the world once a brave party of adventurers undertook a perilous quest to retrieve one of his holy artifacts.
 * This is mostly notable in that, in Greyhawk at least, the rules come from mutual agreement made by the gods of that world, and not by the physical or magical laws of reality that bind them. The gods can choose to interfere in the world at any time if they so desire... but that's counted as explicit permission for one of their opposites to come in and do the same thing without penalty. And usually the interference of the second god involves undoing as much of the work of the first god as possible.
 * An example from Temple of Elemental Evil, Hedrack, the high priest of Iuz, will summon his deity if the fight when the players starts to go badly. St. Cuthbert will then teleport in and take Iuz away so they can fight somewhere private.
 * Of course, none of this prevents the gods from freely providing indirect help to their mortal servants. While the granting of divine magic is the most common way this is done, one of the original justifications for Hit Points in the early editions of D&D was that at least some of the increase in character hit points and saving throws came from the increased divine favor and help they received as they gained levels.
 * One (unproven) theory for why clerics in the Ravenloft setting don't experience as close a connection to their patron deities as those in other D&D settings is that an "Unspoken Pact" exists between the gods and the Dark Powers, by which they've agreed to keep their respective mitts off each others' territories.
 * The Chaos Gods in Warhammer 40000 seem unwilling or unable to directly enter or affect the Materium (unless, possibly, there is a severe instability of the Warp, or a large concentration of Chaos worshipers). They are said to have directly infused Horus with their power, and when he was destroyed by the Emperor, they fled in fear of being harmed. The Emperor himself is worshiped enough to likely be a god within the Warhammer cosmology, but he is limited by the fact that his body is still (barely) alive and confined to an incredibly complex and immobile life support machine, though its implied he is occasionally able to directly help his followers. The Eldar gods were an aversion, as they apparently took part in the war against the Necrons and C'tan. However, after most of them were eaten by Slannesh, of the three who survived, one spends most of his time in an impenetrable Warp matrix, where he advises one of the most enigmatic Eldar factions, the second was broken into pieces (though those pieces are still able to occasionally manifest to provide military aid to the Eldar) and the third is held prisoner by one of the other Chaos Gods as a testing ground for his newest diseases.
 * This also applies to Warhammer Fantasy, where all gods seem pretty much like the Chaos Gods in that they can influence the mortal world, but can't directly enter it.
 * In Scion, the gods have their hands tied on two levels. The first is that the Titans have broken free and are currently storming the Overworld, so the gods have to spend their time fighting them off up there. The second is that if they did manifest on the World, Fate would snap on them like handcuffs. In fact, that's why the gods no longer seek human worship - Fate is a bastard in Scion. This is why the gods have spent so long having children with mortals - Scions are not subjected to the whims of Fate as they are, making them the perfect weapon against earthly Titan plots.
 * In Legend of the Five Rings, it is not the incarnate kami that must accompany Shinsei to defeat the Dark God Fu Leng but rather seven mortal heroes. Shinsei's stated reason is that "fortune favors the mortal man". The unstated reason is that if Jigoku (the Realm of Evil) managed to corrupt the kami Fu Leng into their greatest champion, then what could stop them if all the other kami are Tainted as well?

Toys

 * Mata Nui was shut down with a virus and put to sleep by the Makuta in Bionicle. Then, when he woke up, he was

Video Games

 * Interesting variant from Rayman 2: The Great Escape: Rayman must summon a god who can wipe out the pirates invading the planet. The god, Polokus, is seemingly omnipotent whilst he's on the planet, but it turns out he only has power whilst he's on the planet. In the skies, he would be more helpless than a baby, so it's up to Rayman to stop the pirates on their flying ship.
 * Grandia II, although that's a bit of a spoiler.
 * This is explicitly spelled out as the plot for Mortal Kombat 4; Shinnok, a rogue Elder God who took the Thunder God Raiden a near-apocalyptic attack to take him down before, and who successfully killed off most of the pantheon upon his return, is apparently not powerful enough to fend off a bunch of mortal martial artists.
 * The gods that defend realms suffer from this in that they're supposed to protect their realms from outside threats, but are ill-suited to it. Shown with Raiden and Earthrealm, if an outside realm makes a challenge in Mortal Kombat, the realm challenged can't refuse, and its defender gods can't take part in Mortal Kombat unless directly challenged. If an opposing realm wins 10 Mortal Kombats and invades the defending realm, the defending realm's gods still can't do anything since the invading realm will likely merge the realms, making its gods dominate and the defeated realm's powerless. This is the reason given as to why Raiden initially isn't in Mortal Kombat III, with Earthrealm merged with Outworld, Outworld's gods rule and Raiden is out of job and can't do anything.
 * Blizzard Entertainment's games do this surprisingly often.
 * Starcraft: The Xel'Naga created the Protoss, then the Zerg, which turned against them. The Zerg either killed them all or turned them off to the whole "creating new species" idea and sent them all into hiding. Really more like Neglectful Precursors than gods.
 * Warcraft: The Titans imprisoned the Old Gods on Azeroth and then left. Considering the recent events, they did a pretty poor job at it. They did show some foresight and left the dragons as guardians, but even those weren't immune to the influence of said Old Gods. And of course the Burning Legion is led by one of them who turned evil, and they do not appear to be trying to anything about him.
 * A recent event in World of Warcraft shows that they are becoming aware of how much Azeroth has been corrupted. The proposed solution: "re-originate the planet".
 * On the other hand, there are other gods than the Titans. Elune, some of the less evil trollish loas, the Earthmother, and others are all fairly active in granting their followers powers and in some cases intervening directly. And while it's debatable whether the Holy Light counts as a "god" it's certainly very helpful.
 * Exactly how much some of the above can do is unclear however. Elune's exact nature isn't stated, and exactly what the Earthmother and Holy Light are is also sketchy.
 * In Act IV of Diablo II, the player must . The player is instructed in what to do and how to proceed by , who is  . Of course, given  , the player is probably more powerful than him anyway. Which is a very worrying notion, if you think about it.
 * Valkyrie Profile is a particular offender. The entire point of the game is gathering up human souls to do the fighting for the gods.
 * Of all the series to parody this . . . the fourth game of The Clue Finders introduces Egyptian gods towards the end, who provide the main characters with magical boons to help them beat up an evil god. Said gods would fight him themselves, but the passage leading to him is marked with a sign: "You must be under this height to defeat the forces of Chaos." (And the height is forty feet, no less!)
 * In Persona 2, the conflict between the heroes and the forces of evil is revealed to be a cosmic contest between Nyarlatothep and Philemon. However, whereas the former can (and will) possess people, manipulate them, and take personal action, Philemon can only assist the heroes via the power of Persona and hope for the best.
 * Much of Jade Empire dealt with the difficulties of gods when it comes to controlling events that lie outside their prescribed domain. The most notable is the Water Dragon, who was.
 * Also Forest Shadow, who, despite being a powerful demon, lacked the necessary strength to destroy Mother.
 * The nameless evil feeding on the psychic anguish of those who fell at Dirge could not be banished by any god for a simple reason: As it originated from outside of the world, it had no place in the cosmic order and so no god had the ability to banish it.
 * In Final Fantasy XIII, the Fal'Cie are each "bound to a single Focus and granted finite power to that end". They are not happy about this.
 * In Ever Quest II: Sentinals Fate, the gods cannot face Roheen Theer, the big boss of the expansion because he is the Avatar of the Nameless and can easily destroy gods. It is up to the mortals to kick him back to the void.
 * The first God of War has the Greek pantheon sending Kratos off to kill Ares for them, simply because Gods cannot fight or kill one another. So a mortal directly trained by a God seemed to be their best option. Somewhat off-put, however, by the fact that Kratos himself.
 * In The Legend of Zelda Skyward Sword where we have a prologue mentioning the goddess Hylia fighting and sealing away the Demon King Demise, but while Hylia leaves things for her chosen hero, she herself is nowhere to be seen.
 * In The Legend of Zelda Skyward Sword where we have a prologue mentioning the goddess Hylia fighting and sealing away the Demon King Demise, but while Hylia leaves things for her chosen hero, she herself is nowhere to be seen.

Webcomics

 * The Snarl from Order of the Stick inspired this trope's original YKTTW. It's said in-story that some have speculated that the deities were more vulnerable to the Snarl than a mortal of the same level would've been, but whether this will have any importance has yet to be seen.
 * The main plotline continues this theme, in that the gods cannot act to affect events in the mortal realm and thus must use their agents (clerics, paladins) to get things done. Furthermore, the entire reason this world's Cosmic Keystones exist is because the gods would otherwise need to unmake reality to fix it.
 * Considering that the Snarl killed the entire Eastern Pantheon, it's no wonder the gods don't want to mess with it.
 * In Sluggy Freelance the Goddess of Goodness runs away from the Demon King in terror; she'd already lost to him once before, and that was before she spent a thousand years trapped inside a refrigerator. It falls to Torg, a quasi-ordinary human with a Cool Sword, to fight off the Demon King so they can escape the Dimension of Pain.

Western Animation

 * In Gargoyles, the Third Race have vast godlike power, but their ruler Oberon has magically forbidden them from interfering with mortal life, unless they get permission (or find a loophole that resembles permission). One simple way around this law is to temporarily turn into a mortal human.
 * Oberon himself, on the other hand, is not bound by this, thanks to Screw the Rules, I Make Them. This is how he justifies trying to take Xanatos' and Fox's newborn son Alexander back to Avalon for the Gathering. Of course, since Alexander is descended from the Third Race thanks to his grandmother Titania, he arguably isn't "mortal life".
 * In the Transformers metaseries, Unicron is generally a lot more active and seems stronger than his good nemesis Primus, despite them being more or less equals, because they're both planets and Primus can't act that much without harming his inhabitants, in addition to worries about harming the fabric of reality via action that Omnicidal Maniac Unicron doesn't have.

Real Life

 * Fiction authors in general may be essentially considered omnipotent gods of their fictional universes, since they are completely in control of what happens and what the characters do. However, they are bound by the Obstructive Code of Conduct of "make the work enjoyable", which mean no Deus Ex Machinas, no Out Of Character Moments, etc.