->'''"Jim":''' You can't kill me, either.\\
'''Oma Desala:''' I can fight you.\\
'''"Jim":''' Well, you can't win.\\
'''Oma Desala:''' It won't matter. You won't be able to do anything but fight me back.\\
'''"Jim":''' What're you gonna do?\\
'''Oma Desala:''' Something I should've done a long time ago. ''(she attacks him)'' \\
'''"Jim":''' Oh no... No no noooo!! ''(They vanish in a flash of light)''
-->-- ''Series/StargateSG1''

Sometimes, the BigBad is just too darned evil to be [[SealedEvilInACan Sealed in a Can]]. Perhaps he already was, and it didn't work. After hammering him time and again, our hero eventually realizes that [[ItsUpToYou It's Up to Him]], and carries out the HeroicSacrifice [[FateWorseThanDeath Worse than Death]]: Trapping themselves in [[YinYangClash a duel with the bad guy for all eternity]], thus effectively "sealing" their opponent with themselves as the plug.

If they aren't strong enough, the baddy will escape, possibly [[EnemyWithin using its would-be impediment]] as a SoulJar.

This can also be used as a BackStory, with the release of the BigBad [[SealedGoodInACan also releasing the original hero]].

May invoke SomeoneHasToDoIt. On the other hand, sometimes only their conscience is keeping them on the job.

Sub-trope of HellIsWar. See also KillUsBoth; often overlaps with EnemyWithout and TailorMadePrison. The furthest possible extension of HowMuchMoreCanHeTake. Might be the ultimate duty of a BarrierMaiden.



[[folder:Anime & Manga]]
* ''Manga/InuYasha'': Five hundred years before the story's main feudal setting, the most powerful {{miko}} and the most powerful {{youkai}} of the era fought. Unable to defeat each other, the {{miko}} performed one last desperate spell that trapped their souls for all eternity in a manner that ensured their eternal battle had minimal impact on the world. [[spoiler:The two original souls are almost spent which threatens the Shikon no Tama's continued existence so Naraku offers it the chance for eternal survival: replacement of the original souls with his and Kagome's. Kagome selflessly wishes for the jewel to cease existing, thereby ending the threat and allowing the original souls to find peace.]]
* The plot of ''Manga/{{Naruto}}'' commences with the Fourth using a variant of a sealing technique which summons a shinigami that devours both him and his opponent, damning them to do battle in its belly for all eternity. However, he used another technique with it that made the target (or maybe just half of it) instead become SealedEvilInACan. One wonders how the battle is going between The Third Hokage and Orochimaru's ''arms''.
** It's also mentioned that it might just be a legend, and it probably just kills you. It's not like any of the previous users or victims of the technique, [[UndeadAuthor being dead/eternally sealed in a demon's innards]], are in any position to tell anyone. However, the phrase "summoning contract" implies terms are spelled out between the summoner and summoned. If the contract stipulates the summoner is going into the summoned's stomach, then it will happen if you want the rest of the contract carried out. [[spoiler:We eventually find out from Kabuto that souls being sealed in such a fashion ''do'' have a different fate than those who die normally, as it prevents them from ascending to the normal afterlife on a different plane which in turn prevents them from being brought back by Impure World Resurrection.]]
*** The myth is eventually proved [[spoiler:true when Orochimaru uses his body as a physical vessel for the Shinigami and slits his stomach open. This frees his arms and allows the Hokages to be summoned]].
* ''Anime/XamdLostMemories'' ends with Nakiami sealing herself in the Quickening Chamber for a thousand years to offset the darkness of the Hiroken Emperor.
* In ''Anime/CodeGeass'', it is [[spoiler:subverted. Lelouch seals himself and the Emporer in the Sword of Akasha. It works out pretty well, with Charles having just gained immortality... until Suzaku arrives. Then it culminates with Lelouch destroying his mother and father.]]
** [[spoiler: Of course, if things had gone according to plan, Lelouch presumably would have died of thirst, leaving the immortal Emperor as plain old SealedEvilInACan.]]
* ''Mange/DragonBall''
** In ''Anime/DragonBallZ'', when Gotenks says he won't be able to defeat Buu (actually a trick to distract Buu and a failed attempt at making himself look cooler in front of Piccolo by being a showoff and defeating him at the last second), Piccolo destroys the only door leaving the YearInsideHourOutside PocketDimension they're all in. Subverted in that Buu escapes by ''yelling'' and creating a space rip, and afterwards so do Piccolo and Gotenks by doing the same.
*** Would have been subverted anyway, since Piccolo and Gotenks wouldn't take long to become exhausted and eventually die of dehydration. Piccolo happily points this out: "Our friend could still try to get rid of us if he wants, but [[AndIMustScream then he'd be all alone...]]"
** In the movie ''Dragon Ball Z: Wrath of the Dragon'', the antagonist convinces the heroes to gather the dragon balls to wish that a special music box he brought with him will be opened. He states that it has a trapped hero inside who will foretell of the coming of a great evil. This is all true, but he fails to mention that the great evil was bound to this hero, and by releasing the hero the evil is also released.
* ''Anime/YuGiOh''
** Pharaoh [[spoiler: Atem]] seals himself in the [[spoiler:Millennium Puzzle]] with [[spoiler:Zorc Necrophades]]. Played literally as the two of them spend the next 3,000 years jousting over the most complex RPG known to man: [[spoiler:human history!]]
** It is strongly implied that Yugi and Kaiba will keep on reincarnating and dueling against each other for all of eternity. Summed up in [[WebVideo/YuGiOhTheAbridgedSeries the Abridged Series]]:
-->'''Kaiba:''' Best. Destiny. Ever.
* At the end of ''Anime/PuellaMagiMadokaMagica'', [[spoiler: Madoka makes a wish to destroy every witch before they are born. In a strange sequence, she's told that she'll be locked in an endless battle with every possible witch.]] This is largely an InformedAbility, since we never actually see this happen - [[spoiler: Madoka just causes magical girls to vanish before becoming witches. In fact the only witches we see her destroy are Walpurgis Night and her own witch.]] Notably, the manga adaptation seemed to change the line.
* ''Manga/{{Claymore}}'' does it twice: once for Luciela, a former top warrior of the Organization-turned-Abyssal one, who is sealed away by her sister Raphaela (the two of them eventually become the Destroyer); the second time when [[spoiler:dying Clare]] uses her last strength to seal both the Destroyer and Priscilla in a giant flesh cocoon, trapping them in a battle of willpower... for how long? No one is certain yet.
* Done at the end of the ''Manga/BusouRenkin'' anime. Kazuki uses his Energy Release as a rocket to [[spoiler: launch himself and Victor ''to the moon'']]. Once there, they can't hurt anyone else but can never return [[spoiler: until the rest of the alchemists get around to building a makeshift rocket]].
* Used in ''VisualNovel/{{Tayutama}}''. Mashiro seals herself along with the Tayutai to be there should they escape to recapture them all. The Tayutai aren't exactly evil (well, some are) but more playful and mischevious making them dangerous if let go.
* In ''Manga/OnePiece'', there was once a pirate crew of giants that were basically unstoppable. Then, one day, a little girl asked their two leaders which one caught the biggest fish. The two warriors, Dorry and Broggy, began fighting over it, and as the rest of the crew split up are still dueling even to this day...for ''100 years''...
* In ''Manga/KenichiTheMightiestDisciple'' YAMI (evil) do this to the good guys [[spoiler: by luring their strongest (Hayato Fūrinji) into an equal fight. They fight for several days non-stop. It seems the winner will be the one to scrounge/hunt-down more nutritional food in between attacks, blocks and dodges.]] The stalemate is finally broken when [[spoiler:a fox that Hayato considered eating but spared when he saw that it had a family [[AndroclesLion distracts his opponent at a crucial moment]]. They don't appear to need sleep, however.]]
* Played with to some degree in the second season of ''Anime/DogDays'': Legend tells of how the Hero King Adel had defeated the Demon Lord Valeri and then sealed him along with herself, so that she could make sure Valeri didn't break free. However, [[spoiler: it turns out that this "demon king" was the brother of the queen who summoned this Hero King, and he took part in fighting the demons that plagued the land at Adel's side. He took on the name of Demon King as a joke, then occasionally caused trouble to remind the complacent of the threat, and in the end both of them willingly sealed themselves together so that they could help if a new crisis occurred.]]
* This ''may'' have happened at the end of ''Anime/TurnAGundam''. At the end of their final duel, the Turn A and the Turn X [[spoiler:manages to inflict a MutualKill on each other, causing their respective Moonlight Butterfly systems to go berserk and encase both mobile suits into a cocoon-like shell]]. Considering that they also use the same nanomachines to repair themselves and the Turn X demonstrated at least some degree of [[SapientSteed independent will]] when it came to fighting the [[WorthyOpponent Turn A]], [[FridgeLogic it is possible that the two machines attempted to repair the damage they suffered by mutually trying to consume each other for raw materials, endlessly breaking down the other to repair themselves]].
** As for their pilots, Loran managed to get far enough away in time. [[BigBad Ghingham]] wasn't so lucky - and since he's the pilot of the Turn X, [[AndIMustScream its nanites will keep him alive indefinitely]].

[[folder:Comic Books]]
* The ComicBook/JusticeSocietyOfAmerica did this when they fought the Norse Gods, to prevent UsefulNotes/AdolfHitler from destroying the world with TheSpearOfDestiny. {{Justified|Trope}} as the battle was Ragnarok, which ended like this.
* Once, after Doctor Doom came within an inch of wiping out the ComicBook/FantasticFour, Reed decided the only way to keep his family safe from Doom for good was to trap the two of them in an inescapable pocket dimension. Knowing the team would never allow him to do this, Reed tried to distract them and push them away emotionally, but they managed to stop him anyway (unwittingly letting Doom escape). The kicker? Doom was ''already in Hell'' when Reed resorted to this -- with Doom's record, he didn't trust the devil to hold him.
** and he was right! The comic shows Reed interrupting Doom in hell just as Doom was beginning to put a plan in motion.
** Another FF storyline, when they faced Reed's time traveling evil grandson Hyperstorm, ended with Hyperstorm trapped in a pocket dimension with Galactus, constantly blasting him with his own limitless energy to keep him at bay, but with Galactus feeding off the blasts. At the time, the FF assumed the two might be stuck that way forever, with Ben commenting that it was an awful fate even for a crumb like Hyperstorm. However, Galactus has since reappeared, which implies that Hyperstorm either found a way to escape or else Galactus ate him.
* In the ''[[ComicBook/TheTransformers Transformers Generation 1]]'' comic books, this is how the planet Cybertron and the [[PlanetEater planet-eater]] [[GodOfEvil Unicron]] came to be -- he and Primus were elder gods who battled across several planes, with the single-mindedly destructive Unicron winning the battle. As a last resort, Primus led Unicron from the astral plane into what is our dimension and directly into two metal asteroids, trapping both of them for eternity. While Primus turned his asteroid into the planet Cybertron, Unicron managed to turn his asteroid into a [[EldritchAbomination transforming planet-sized robot.]]
* In Creator/MarvelComics's what-if of their crossover ''AtlantisAttacks'' (in ''ComicBook/WhatIf'' v2 #25), Set the Serpent God succeeds in freeing himself from interdimensional exile and returns to Earth, killing most superhumans and converting the rest (as well as regular humanity) to serpent people. One by one the remaining heroes and villains fall, and all hope seems lost, until ComicBook/{{Quasar}} arrives on the scene, having just escaped Set's dimension (where he'd been lost since the Serpent God escaped). He's been granted the ComicBook/CaptainUniverse power, which combined with his Quantum Bands to make him Set's equal. He opens the recently deceased Comicbook/DoctorStrange's [[AmuletOfConcentratedAwesome Amulet of Agamotto]], using it to pull them both into a pocket dimension where the two of them will battle forever. Unfortunately, although Set has been removed from the equation, [[DownerEnding he's had time to reproduce...]]
* Another example from Marvel - after [[ComicBook/TheMightyThor Odin]] got KilledOffForReal in a battle with Asgard's arch-enemy Surtur, their battle continued on the doorstep of the afterlife. Every day Surtur tries to reach a part of his spirit that will allow him to revive in the real world, and every day Odin kills him and then dies from terrible wounds, just for their injuries to disappear by the next day, so that their struggle may continue until the end of time. Odin doesn't mind though, seeing this fate as an atonement for his old misdeeds and mistakes.
** This actually happened several times. If Odin is not around it's a safe bet that he is sealing some evil in a duel. The most common of those evils is Surtur, but he also did this with Cul for example, albeit in a slightly more cultured way as [[SmartPeoplePlayChess they played]] [[TheChessmaster chess]] for "eternity" (which lasted from the end of Comicbook/FearItself to Comicbook/OriginalSin). To be fair this ''is'' a fairly reasonable way to keep the nigh omnipotent [[PhysicalGod sky-father]] from breaking the story.
* During the prestige format run of ''ComicBook/{{Legion of Super-Heroes}}'', the Legion finally "defeated" the Time Trapper (the AnthropomorphicPersonification of the Cold Universe cosmic model) by unleashing the Infinity Man (the AnthropomorphicPersonification of the Cyclical Universe cosmic model) on him. The two end up locked in eternal combat with each other.
* An Elseworlds posits that Franchise/{{Batman}} and the Joker will be fighting each other in one form or another for eternity. ''WesternAnimation/BatmanBeyondReturnOfTheJoker'' also supports this notion, [[spoiler:at least until Tim kills him]].
* This is how Palpatine is ultimately defeated in ''Franchise/StarWarsLegends'': Empatojayos Brand [[spoiler:sacrifices himself so he can carry Palpatine's spirit away from the universe and in the custody of every Jedi who has ever lived, never to be resurrected again]]. He doesn't have to undergo FateWorseThanDeath himself, fortunately, but the effort of carrying away a spirit of pure evil does cause his own spirit a great deal of suffering.
* An issue of the Dark Horse Franchise/{{Godzilla}} comics featured Gekido-Jin, an invincible demon who is imprisoned [[TakenForGranite in a statue]] by a warrior whose soul fights his soul for all eternity. When Godzilla decides to go sightseeing on the (still inhabited) island Gekido-Jin is imprisoned on, a minor character sacrifices himself to free the ancient warrior from his eternal battle and let Gekido-Jin live long enough to drive Godzilla off, at which point the man who sacrificed himself takes up the spirit-duel with the demon.
* In the fourth issue of ''ComicBook/GodzillaInHell'', Godzilla finds himself trapped in a walled city replica of Tokyo in the afterlife, eternally fighting King Ghidorah and Destroyah, as whenever any of them are killed, they immediately come back to life. Godzilla tries to destroy the wall around the city, but finds that his atomic breath isn't able to damage it. [[spoiler: He manages to destroy the wall by tricking Destroyah and King Ghidorah into firing at the same spot as him, which is enough to break through. When he does, King Ghidorah, Destroyah and the city immediately vanish.]]
* At the end of the ''Crimson'' comic, one half of the BigBadDuumvirate, the king of dragons, who it's implied can never be truly killed (and thus it's implied could otherwise always recreate [[OurDragonsAreDifferent the dragon race]] in time), is dealt with this way when it and the current {{reincarnation}} of Saint George (yes, that one) are trapped in a PocketDimension to fight each other forever. [[spoiler:Actually subverted in that {{God}} intervened, so that the dragon king would be FightingAShadow for eternity, while the ''real'' Saint George, after centuries of service culminating in a HeroicSacrifice, is finally taken to [[{{Heaven}} his final reward]].]]
* While not exactly "sealed", it's revealed in the ''ComicBook/SonicTheHedgehog'' series that the Xorda, aliens that eradicated most of the humans when Mobius was known as Earth, and [[VideoGame/ShadowTheHedgehog Black Arms]], aliens seeking to feast on Mobius' population, are locked in a vicious war with no end in sight over their claim of Mobius.
* ''ComicBook/NemesisTheWarlock'': The final arc concludes with Nemesis stopping Torquemada from activating his "[[WeaponOfMassDestruction Final Solution]]" (a bomb designed to exterminate every alien and all humans who came into contact with an alien) by drawing the explosion into both himself and Torquemada, who is also vulnerable after Nemesis scratches him with his claws. Nemesis and Torquemada merge with the Blitzspear into a single entity which roams the cosmos for billions of years into the future.
* The Shaggy Man is a mindless beast with incredible strength and seeming immortality. In its first appearance, it was finally defeated when Franchise/TheFlash suggested to its creator Dr. Andrew Zagarian to create a second Shaggy Man. While the two creatures fought, the Justice League sealed them into a deep pit. Of course, villains eventually found the pit and freed them.

[[folder:Fan Works]]
* Subverted in the ''TabletopGame/HunterTheVigil'' fanfic [[http://www.fanfiction.net/s/2769469/1/How_I_Learned_To_Hate_Hiking "How I Learned to Hate Hiking"]]. One character thinks that his yearly battle against a nature spirit is all that keeps... something bad from happening. Except that the enemy is the Spirit of [[HumansAreBastards Nature Getting Beaten by Civilization]], so it uses this trope as a power source for an empathetic attack on humanity.
* In the last few pages of ''Fanfic/{{Heartless}}'' before the author went to work on other stuff(Let it be temporary, let it be temporary) Drich was sealed in a pocket dimension with an incomplete Naruto Physicalgod Juubi, unlike most examples it's an unstable equilibrium but it just needs to last for long enough.

[[folder:Films -- Live-Action]]
* Used as a BackStory in ''TheSorcerersApprentice'' with both the Grimhold (with Morgana and Veronica) and with the Chinese vase in which Balthazar and Hovard get locked for 10 years.
** It's implied that Balthazar and Horvath didn't fight in the vase, as Horvath claims he was ''extremely'' bored, reading the same (poorly-written) essays on Napoleon over and over. You don't really have time to do that if you're busy fighting. At least Balthazar had his Incantus.
* One of the many alternate endings for ''Film/FreddyVsJason'' had the pair locked in eternal battle in an arena in Hell.
* In ''Film/PiratesOfTheCaribbeanTheCurseOfTheBlackPearl'', Barbossa lampshades after he and Jack are both rendered immortal, observing they ''could'' keep fighting until the end of time. The duel itself manages to end when [[spoiler:Barbossa becomes mortal again.]]
* In ''Film/DoctorStrange2016'', this is how [[spoiler:Strange convinces Dormammu to give up on conquering Earth. He enters the Dark Dimension and brings a time-loop spell with him that activates every time Dormammu kills him. Dormammu tells Strange that he can never win, and Strange responds that he doesn't have to. He can just keep losing forever and Dormammu can just keep defeating him forever, but Dormammu will never be able to do ''anything else'' for all eternity]].

* In ''[[Literature/NightWatch Twilight Watch]]'', Anton, TheHero, has to go up against an uber-powerful vampire. He's given various spells by the forces of both light and darkness, as well as the Inquisition. The inquisitors' ultimate spell "Sarcophagus of Ages" encases the target and the caster in a tomb [[AndIMustScream they will be alive for all eternity]]. Anton doesn't use the spell this time, but it is revisited a couple novels later. The sarcophagi look like white marble domes as big as two-storey houses, drifting in nothingness of the DarkWorld. And there turn to be one or two ways to leave them.
** After finally using it, Anton figures that they will remain in the Sarcophagus until the end of time... at least he hopes the end of time will also end the Sarcophagus and their suffering. [[spoiler:The Tiger ends up pulling him out to save itself, and Arina is retrieved in the following novel in order to save humanity]].
* In ''Literature/TheBookOfTheDunCow'', [[TheEeyore Mundo Cani]] drives the [[BigBad Wyrm]] back into its prison inside the Earth where it's said that not only does he keep fighting to prevent Wyrm from invading the upper world, but that the souls of the brave go to join him in the battle when they die.
* In Creator/RickRiordan's ''[[Literature/TheKaneChronicles The Red Pyramid]]'', the main characters discover that [[spoiler:the cat goddess Bast]] was released from an artifact that also contained [[spoiler:the serpent of chaos Apophis]] because she was losing the battle, but now that she's free she can help stop Set from completing his plans with the Red Pyramid.
* In [[Literature/TheSecretsOfTheImmortalNicholasFlamel The Sorceress]], Aoife willingly triggers this to stop Coatlicue from rampaging across the myriad worlds.
* In ''Riddle of the Seven Realms'' by Creator/LyndonHardy, Astron can only stop [[spoiler:Palodad]] from destroying the multiverse by pushing the BigBad into the flame that's tearing a hole in the daemonrealm, then [[HeroicSacrifice jumping through himself]] and pulling the source of flame in after him. [[spoiler:Subverts this trope, as Nimbia is able to create a new pocket-world within the Void to encase Astron, then retrieve him.]]
* This is how the [[TabletopGame/DungeonsAndDragons Penhaligon trilogy]] ends: Fain Flinn will fight Teryl Auroch forever to keep him from destroying Mystara.
* This is how Superman wins against Saturn, The Devil's Agent on Earth in the novel ''Literature/MiracleMonday'': by threatening to spend ''every second'' of the rest of his life fighting him and undoing all his evil deeds. ([[spoiler:Actually, the book makes clear that Saturn could've won easily and destroyed the Earth if he wanted- but neither of those were his goals; he wanted to break Superman's spirit and end the hope he inspires in humanity. But just the realization that Superman would ''never'' give up effectively caused his defeat due to the laws that govern demons]].)
* At the end of ''Literature/ANightInTheLonesomeOctober'', Lawrence Talbot pounces on the evil Vicar and they both go tumbling through the otherworldly gateway, which seals behind them. This not only traps the Vicar where he can no longer open the way for an EldritchAbomination invasion, but also confines Talbot somewhere where he can no longer harm people as a werewolf.
* A variant in the Creator/DrSeuss story ''The Zax:'' A North-Going Zax and a South-Going Zax bump into each other, and each is too stubborn to go around the other, since this would require them to move slightly to either the east or west. After a brief argument the two are simply stuck glaring at each other, as years pass and other people build highways around them.
* In ''The Golden Cat'' - the sequel to ''TheWildRoad'' - the mentor character and the villain from the first novel are locked into this.
* This is how [[spoiler: the Dreadking]] is defeated in the final volume of ''Literature/TheRiftwarCycle''. [[spoiler: The Dreadking]] is an EldritchAbomination, personification of the UltimateEvil, that is too powerful for any ordinary magic to contain and will ultimately consume the entire universe, past, present, and future, if freed. Against it are set [[TheArchmage Pug]] and [[EmpoweredBadassNormal Tomas]], a human who possesses the power of a [[AbusivePrecursors Valheru]]. To fully tap into that power, Tomas has to let himself be subsumed by the Valheru personality, an AboveGoodAndEvil demigod warlord, but that's the only way he can be powerful ''enough'' to grab [[spoiler: the Dreadking's]] undivided attention. So Tomas unleashes his SuperpoweredEvilSide, goes in to fight [[spoiler: the Dreadking]]- and then Pug [[spoiler: uses all the power he can to trap them both eternally in that moment, preventing either from becoming a threat to the world and warding away the Dread from the living world for good- at the cost of his own life and much of the surrounding geography]].
* In ''Literature/TheRhesusChart'' by Charles Stross. A powerful vampire sorcerer attacks the Laundry and Angleton (an EldritchAbomination SealedInsideAPersonShapedCan) apparently performs a HeroicSacrifice to stop him, but they NeverFoundTheBody as they're sealed inside a dome-shaped protection ward too powerful to even approach. Earlier another vampire had demonstrated the use of such a ward to keep his victims alive so they can be fed upon.
* In ''Literature/TheGuardiansOfChildhood'', Pitch was originally defeated when Nightlight speared him and trapped them both in the depths of the Earth.
* In the third ''Literature/{{Mistborn}}'' novel, [[spoiler: Vin]] spends some time in this situation with Ruin after [[spoiler: she becomes the new Preservation.]] Both of them are theoretically so powerful that they can do almost anything you can imagine, but since they each directly oppose every single one of the other's goals, everything one tries to do the other one will immediately counteract, rendering them both functionally powerless.
* In ''LightNovel/HighSchoolDxD'' [[spoiler:Trihexa]] is sealed in this way. [[spoiler:Numerous gods and god-level beings seal themselves away with Trihexa in order to keep it occupied and prevent it from breaking out. Unlike most examples of this trope, the large number of fighters on the good side means that not all of them have to fight at the same time, and they therefore have time to communicate with the outside world.]]

[[folder:Live-Action TV]]
* ''Series/StarTrekTheOriginalSeries'': In the episode "The Alternative Factor", Sane!Lazarus asks Captain Kirk to imprison him and his [[OmnicidalManiac evil, normal matter counterpart]] in a time corridor, where both will remain fighting in a form of living death for all eternity. Since refusing to do this would put the universe at risk, Kirk reluctantly agrees to carry out this plan. FridgeLogic kicks in because, unlike almost every other example of this trope, Lazarus is not a god-like being who can only be opposed by his opposite half, he's just an ordinary man with slightly better advanced technology. There's nothing to stop them from simply shooting the evil Lazarus, or at least handcuffing him to a pipe.
* ''Series/StargateSG1'': This is the preferred way to deal with an Ascended being, as otherwise Ascended beings can only be killed if enough of them team up against the other side to overpower them. But otherwise two equal ascended can nullify each other like this. Oma Desala does it in season 8 to neutralize "Jim", AKA [[spoiler:Anubis]]. It occurs again at the end of "The Ark Of Truth" when Adria (who had access to all the Ori's collective power and was thus more powerful than the assembled Ancients) is depowered by the Ark turning her believers away from her, leaving her on par with other Ascended. [[spoiler: Morgan [=LeFay=] engages her in combat to take her out permanently.]]
* ''Series/DoctorWho'':
** A nod to this trope was seen in "Last of the Time Lords". After the decisive defeat of TheMaster, the Doctor was not willing to execute the only other member of his species in existence. So he volunteered to live up to this trope, keeping the Master confined in the TARDIS for all eternity or until he reformed. The Master prevented this by committing suicide (or at least refusing to come back from the dead).
** While most details about it have not been revealed; certain references to the Time War make it a potential candidate, where the evil locked away is the entire Dalek race with the time lock as the barrier keeping them fighting the Time Lords, and only the Time Lords, in an unending loop where the dead are brought back just to die all over again. [[spoiler: Then the unending war drove the Time Lords just as violent and insane as the Daleks, making them both sealed evils keeping each other bottled up]]
---> '''Jack:''' One minute they're the greatest threat in the Universe, the next minute they vanished out of time and space.
---> '''Doctor:''' They went off to fight a bigger war. The Time War
---> '''Jack:''' I thought that was just a legend.
---> '''Doctor:''' I was there. The war between the Daleks and the Time Lords, with the whole of creation at stake.
** This is the ending of "The Eaters of Light", as Kar and the surviving Roman legionaries charge into the portal to fight off the Eaters for the [[YearInsideHourOutside lifetime of the universe]]. The Doctor nearly did it himself, but had a MoreExpendableThanYou pulled on him.
* In the season 5 finale of ''Series/{{Supernatural}}'' Sam combines this with SealedEvilInACan by inviting [[TheDevil Lucifer]] to possess him, then trying to keep control of his body long enough to jump into the Can they have no chance of getting Lucifer into otherwise. [[spoiler: Sam does end up jumping into the cage, with [[ArchangelMichael Michael]] (In [[CainAndAbelAndSeth Adam]]) falling in with him.]]

[[folder:Tabletop Games]]
* In ''TabletopGame/MagicTheGathering'''s "Innistrad" pack, the whole plot is driven by the fact the archangel Avacyn got herself trapped in the Helvault alongside her demon nemesis Griselbrand.
* In the ''TabletopGame/{{Eberron}}'' setting, the Church of the Silver Flame was founded around a Lawful Good energy phenomenon supposedly created when Tira Miron and a couatl merged together to trap an archdemon inside of it. Tira's voice is often heard from the flame, though there are heretical rumors that the couatl and demon sometimes speak from it also.
* ''TabletopGame/LegendOfTheFiveRings'' does this with Hida and his son, and later with Iuchi Karasu and Kuni Yori.
* This is the origin of the Calim desert in the Forgotten Realms ''TabletopGame/DungeonsAndDragons'' setting, in the form of a never-ending duel between a djinn and efreet lord.
* Sisyphus shows up in the FantasyKitchenSink that is ''TabletopGame/{{Scion}}'', and his specific case is subverted - when the Titans broke out, a rock took out the top of the mountain, letting him finally finish the job. As a result, he is now NighInvulnerable, possesses great power... and has no clue which side to sign on with. (If the Titans win, the world is screwed; on the other hand, three thousand years of pushing a boulder is a ''long'' time...)
* A spell card called [[http://yugioh.wikia.com/wiki/Different_Dimension_Gate Different Dimension Gate]] emulates this trope in the ''TabletopGame/YuGiOh'' card game; it allows the user of the card to banish an opposing monster, so long as he banishes one of his. (However, unlike most examples of this Trope, both players get their monster back if the card is destroyed, although there are ways around this.)
* ''TabletopGame/{{Warhammer 40000}}''
** In prior editions of the game, to stop the Thirteenth Black Crusade, Eldrad Ultharan had to trap his soul in a battle with the Chaos spirit powering Abbadon's Planet Killer. There was significant disagreement about whether he was dead or not, but given that it's now been retconned there's not much to argue about anymore.
** Similarly, an Ork vessel once crashed on a planet in the Eye of Terror. Everyday, umpteen million Orks awaken and wage unending battle against countless hordes of demons until they die horribly, only to reawaken the next day. The Demon Lord in charge of the planet uses this to train and harden his army, except they keep getting killed and weakened; the Imperium thinks of this as a FateWorseThanDeath; the Orks consider this ''[[ProudWarriorRace paradise]]''.
* On the ''TabletopGame/{{Warhammer}}'' fantasy side, Caledor Dragontamer and his disciples have been trapped in the Vortex on the Isle of the Dead, where they have been stuck for at least 3000 years, ceaselessly performing a magic ritual designed to pull the excess magic out of the world and prevent (or at least massively delay) the victory of the Chaos Gods. In an interesting variation, the Chaos Gods are not on, or even touching the world near the Isle of the Dead (the closest being the overlap between the "real" world and the Realm of Chaos at the north and south poles), nor is any champion of Chaos present. It just happened to be where Caledor chose to set up his world-spanning spell.

[[folder:Video Games]]
* ''VideoGame/KingdomHeartsBirthBySleep'' reveals in the secret ending that Terra is doing this with Master Xehanort as of the end of the story, both of them fighting for control of Terra's Heart. Of course, a year or so later [[FanNickname Terranort]] splits in two, his Heart becoming [[TheHeartless False Ansem]] and his Body becoming Xemnas; what they've been doing since then is anyone's guess.
** ''VideoGame/KingdomHearts3DDreamDropDistance'' indicates that [[spoiler:both Ansem and Xemnas know about Master Xehanort, and their defeat recreated him; what has become of Terra in the decade since then is unknown.]]
* ''Franchise/{{Pokemon}}'':
** Wobbuffet was given the ability Shadow Tag in Generation III. This prevents the opponent from switching out. If two Wobbuffet battle each other, then the battle would last until they run out of attacks and are forced to use Struggle. However, a hold item called Leftovers would heal the Wobbuffet every turn if the Wobbuffet was holding it, and since it ended up healing more damage than Struggle was dealing, having two Wobbuffet in battle both holding the Leftovers item would result in a never-ending battle, causing Wobbuffet to become the first non-legendary Pokémon to be banned from official tournaments. This was fixed in Generation IV, where Shadow Tag will fail to work if the opponent also has Shadow Tag, and Struggle doing 1/4 of maximum HP in damage with recoil.
** The infamous "[[BlatantLies Fun]]bro" strategy, banned in most non-official competitive circles, created an outcome like this. A Slowbro can trap an opponent with Block and then use Slack Off and Heal Pulse to not only prevent itself from fainting indefinitely but also keep their ''opponent'' from fainting [[labelnote:*]]While keeping the opponent alive is mainly just to [[{{Griefer}} troll]], it does technically have competitive merit by denying the opponent the ability to ever send in a different, more powerful Pokémon.[[/labelnote]] due to Struggle's aforementioned recoil damage. The Slowbro itself never runs out of moves thanks to using a Leppa Berry to renew its attacks periodically, and Recycle to infinitely regenerate the berry. Unless the captured foe has a way to defeat Slowbro faster than it can heal itself, it creates an endless battle where the only winner is whoever doesn't grow bored and forfeit first. Other "Fun___" strategies have been discovered, but Slowbro remains the most iconic perpetrator.
* Blizzard Entertainment likes this trope.
** It begins in ''Videogame/{{Diablo}}''. This is what the protagonist attempts after slaying Diablo's current avatar. Needless to say, it didn't work.
** In ''[[Videogame/{{Diablo}} Diablo II]]'': In the backstory (actually already in the first game's manual), Tal Rasha used his own body as an extension of a soulstone to imprison Baal. He is [[GrandTheftMe possessed]], and has to be tied up and magically bound in a tomb, his spirit fighting Baal's for eternity. Or until Marius came along in the second game and tugged on the ringpull [[NoGoodDeedGoesUnpunished in an attempt to rescue Tal Rasha.]]
-->'''Tyrael:''' [[DontTouchItYouIdiot No! Don't do it!]]\\
''(pop goes the soulstone)''\\
'''Tyrael:''' Fool! [[OhCrap You have just ensured the doom of this world!]]
** In ''VideoGame/WorldOfWarcraft'', [[http://www.wowpedia.org/Arellas_Fireleaf Arellas Fireleaf]], a minor character of whom we only know what is written on a statue, is said to be "Locked in eternal combat with the Necromancer Diesalven".
** A far more important example, if it is one: At the end of the Icecrown Citadel raid, Bolvar Fordragon dons the helmet of the Lich King to contain its power. This may mean that he's in there together with the original Lich King, Ner'Zhul, or that Ner'Zhul was destroyed or weakened to insignificance too and Bolvar is only keeping the armies of the Scourge at bay through his new control over them.
* The cancelled ''VideoGame/{{Ultima}} X: Odyssey'': When The Avatar sealed himself and his EnemyWithout, The Guardian, behind a wall of life to destroy them both with an armageddon spell, The Guardian managed to merge with him. They then struggle for dominance with ThePowerOfFriendship backing them up.
* Blue's ending in ''VideoGame/SagaFrontier'' appears to be him locked in an eternal battle with Hell's Lord after the portal to Hell is sealead away and the battle cuts away to a "The End" screen abruptly. WordOfGod says he teleported out, but that's not nearly as cool...
* ''VideoGame/QuestForGloryIV'' has this with Erana and Avoozl. [[spoiler: Ultimately, the hero's reason for being summoned is to finish summoning Avoozl, breaking the stalemate in favor of the EldritchAbomination, only to free Erana who, now unbound, can banish Avoozl properly.]]
* ''VideoGame/FreedomForce vs. The Third Reich'': Manbot and the Wraiths of Chaos.
* ''VideoGame/{{Persona 3}}'': [[spoiler:At the end, the Main Character [[HeroicSacrifice sacrifices himself]] to transform [[BarrierMaiden into a barrier]] that keeps the two resident {{Eldritch Abomination}}s from meeting each other and [[TheEndOfTheWorldAsWeKnowIt destroying the world]]]].
* In ''Franchise/StarWarsLegends'', Jedi Master [[http://starwars.wikia.com/wiki/Hoth_%28Jedi%29 Lord Hoth]] uses this method to defeat the Sith Lord Kaan; forcing Kaan to activate a superweapon that trapped their spirits, and those of their followers, in eternal conflict and torment. Until [[VideoGame/DarkForcesSaga Kyle Katarn]] released them, at least. This is all the work of Darth Bane, who sought to destroy Kaan's followers in order to remake the Sith in a superior form. [[XanatosGambit Killing Hoth and numerous other Jedi was just a bonus, and they would be dead regardless of the initial fight's result.]]
* In one of the books based on ''VideoGame/CityOfHeroes'', [[TheCape Statesman]] and [[BigBad Lord Recluse]] compare themselves to Sisyphus and the rock. Statesman wonders which one is which...
* In ''VideoGame/LostOdyssey'', this is the fate [[BigBad Gongora]] wanted to avoid, cue the 30 years long EvilPlan. Of course, in the end, making 4 powerfull immortals very pissed backfire at the end.
* As described by [[WebVideo/TheSpoonyExperiment Noah Antwiler]], ''Film/ETTheExtraterrestrial'' on the UsefulNotes/Atari2600 vs. the Player is pretty much this.
* In ''VideoGame/CastlevaniaSymphonyOfTheNight'', this is a brainwashed Richter Belmont's motive for reviving Dracula:
-->'''Richter Belmont:''' Count Dracula rises but once every century, and my role is over. If I can resurrect him, then the battle will last for eternity!
** The motivation seems slightly different; as the above quote shows, Richter doesn't want to do this to trap Dracula (vs. letting him free); he wants to do this to continue the fight (vs. the fight being over).
* Towards the end of ''VideoGame/BreathOfFireII'', it turns out that the sleeping, giant dragon near the village of Gate is actually a Dragon Clan member (Ryu's mother, in fact) who turned herself into that form to keep the game's HellGate closed and prevent the release of Death Evan. Slightly subverted in that you ''must'' relieve her of this task by going through the HellGate and defeating the BigBad. If you choose not to, Death Evan eventually overwhelms her defenses and bursts to the surface, resulting in a NonstandardGameOver.
** Even after Death Evan is defeated, demon gods don't just die, so the HellGate has to be closed again to guard against his future return. If you failed to unlock the flying Township, Ryu himself has to take his mother's place. If you did unlock it? [[ColonyDrop Turns out that a giant airship works just as well as a giant dragon for sealing a hole]].
* [[spoiler:Shurelia]]'s HeroicSacrifice in ''VideoGame/ArTonelicoMelodyOfElemia'', to seal the BigBad Mir. [[spoiler:You get the chance to [[DefiedTrope defy]] this. If you do, both Shurelia and [[WoobieDestroyerOfWorlds Mir]] get better.]]
* ''VideoGame/MegaManBattleNetwork 6'' has an interesting twist: There were ''two'' great beasts ravaging the world, so they enticed the beasts into fighting ''each other'' and then blocked off the battleground as best they could so no one would interfere or get caught in the crossfire (obviously that didn't work).
* ''Franchise/TheLegendOfZelda'':
** In ''VideoGame/TheLegendOfZeldaSkywardSword'', it's revealed that the ''Master Sword'', the iconic weapon of the series, is this. [[spoiler:The sword's spirit Fi takes it upon herself to seal Demise's soul within herself. Demise manages to unleash one last parting shot by unleashing a curse on Link and Zelda that would doom them to face an incarnation of his hatred whenever they are reincarnated. That incarnation turns out to be the series BigBad Ganon.]]
** In ''VideoGame/TheLegendOfZeldaBreathOfTheWild'', the only reason why Calamity Ganon hasn't completely destroyed Hyrule already is because [[spoiler:Princess Zelda]] has been busy keeping him sealed inside Hyrule Castle for the past 100 years.
* For the very last fight of ''VideoGame/DuelSaviorDestiny'' Taiga decides to invoke this one against [[spoiler:God himself]] and proceeds to travel to a different dimension and do just that. Due to previously mentioned time distortions between realms, he goes on to win the fight several million times without being able to actually kill his opponent, which he knew would probably happen. [[spoiler:Still, he manages to put a seal over God eventually, letting him return home.]]
* The ending to ''VideoGame/{{Doom}} 64'' has shades of this; after once again entering Hell to stop the Demons from attacking humanity, the Doom Marine decides to stay there for good, in order to prevent them from rising up yet again.
* Calypso's ending in ''VideoGame/TwistedMetal 4'' [[spoiler:has him demand the return of the ring that holds the power to grant wishes, and implicitly, the competition itself. When Sweet Tooth refuses, Calypso attacks him and wrenches the ring off his finger - whereupon the souls within it explode out. Later, a young boy finds the ring, and sees Calypso and Sweet Tooth still battling each other within it...]]
* In ''VideoGame/TheElderScrollsVSkyrim'', after inadvertently waking the Dragon Priest, Morokei, in the depths of Labyrinthian, [[spoiler: Savos Aren]] contained him by enthralling his dead colleague's spirits in an eternal magical duel, preventing Morokei from being unleashed upon an unsuspecting Skyrim. He feels guilty about it to this day; the nature of the spell meant he couldn't sacrifice himself in their place.
** The Nord ruin of Valthume is the tomb-turned-prison of the dragon priest Hevnoraak, who made plans for his own resurrection as a lich. A Nord warrior named Valdar discovered Hevnoraak's plans, however, locking himself inside the tomb and binding himself to the dragon priest to prevent him from returning for thousands of years. By the time the Dragonborn finds him, Hevnoraak is close to overthrowing Valdar, forcing them to team up and accelerate the resurrection and kill him again before he can escape.
* In the backstory to ''VideoGame/BlazBlue''; Once Yuuki Terumi broke free of the geas which kept him under control as one of the Six Heroes and murdered their magician, Nine, Hakumen, their leader, arranged a trap which sealed both Hakumen and Terumi in The Boundary outside reality. Unfortunately, someone was foolish enough to let Terumi out.
** Ragna the Bloodedge gave himself his title because the previous owner of his BadassLongcoat and {{BFS}} was a hero named Bloodedge. In the distant past, Bloodedge fought the Black Beast in order to distract it long enough for humanity to learn how to use Ars Magus so they could kill it. He managed to last an entire year before the Black Beast finally killed him. [[spoiler:Also, he was a time-travelling Ragna with amnesia, meaning Ragna unknowingly took his title from himself]].
* ''VideoGame/SoulSacrifice'' is a game that lives up to its title in almost every sense of the word, such as with this trope's multiple appearances with [[BigBad Magusar]], each with a different format. At the end of [[PortalBook the writer's journal]], [[spoiler: he explains that Magusar kept ''him'' in this loop with his immortal blood each time he was defeated until he was reduced to the form of the fleshy, deformed Librom. One of the game's endings is a reflection of this, with you reviving Magusar in an endless loop, as containing Magusar's soul would slowly erode over one's identity , same as what happened to the host you're fighting.]] Two mental variations of the trope occur as well, as Magusar's [[spoiler: present host fights both against him, but in the [[UpdatedRerelease ''Delta'' expansion]], also the [[EternalRecurrence Gods of Eternal Recurrence]]. After beating on Magusar enough that he considers you a threat, he lets go so you can put him to rest.]]
* In ''VideoGame/{{Undertale}}'''s most evil ending, Sans gets into a battle with [[spoiler: the Fallen Child, a.k.a. [[VillainProtagonist the player character]]]]. Sans knows [[SensingYouAreOutmatched he can't possibly win]], but he also knows [[HeKnowsAboutTimedHits that battles in the game use turns]]. So, by refusing to end his turn, Sans expects to trap his foe in battle until the end of time. [[spoiler:Unfortunately for Sans, RealityEnsues when his BrilliantButLazy tendencies come back to bite him. By using so much of his effort and energy in the battle, he ends up falling asleep after only a few minutes of his turn, allowing the Fallen Child to kill him.]]
** Earlier in the game, if the player is NOT on the path to the worst ending, Mad Dummy, who is normally invulnerable to damage, threatens to do the same thing after he runs out of attacks, but he gets driven off by Napstablook.
* In [[UndeadChild Peketo's]] ending in ''VideoGame/TheBlackHeart'', Final refuses to give Peketo the titular heart because he's a dangerous psychopath. He tries blowing him up, but he reappears almost immediately, explaining that all the deals he made with the dead before he was killed have rendered him basically immortal. Faced with this, Final instead summons [[AbusiveParent Peketo's Father]] who was killed by his son at the begining of his story and because of similar deals with the dead, has ended up becoming a similar undead abomination like his son. Needless to say, neither of them is pleased to see the other so they engage in battle. Final muses that since neither of them can be killed, they are basically stuck fighting forever.
* The three Goddesses in ''VideoGame/FinalFantasyVI'' freeze themselves into separate statues after seeing the havoc caused by the War of the Magi waged in their name, with the statues positioned in such a way that their respective magics cancel each other out. And it was[[spoiler:Kefka moving the statues out of alignment that caused their magic to lose control, causing TheEndOfTheWorldAsWeKnowIt.]]
* ''VideoGame/FateGrandOrder'': In the Shimosa Province event, this briefly happens when UsefulNotes/MiyamotoMusashi and UsefulNotes/SasakiKojiro have their legendary duel. Musashi's sword style is the embodiment of "Zero" while Kojiro's sword style is the embodiment of "Infinity". The resulting YinYangClash creates a RealityBreakingParadox that draws them into a pocket dimension. The narration implies this is a timeless space where the two would fight for eternity with no conclusion. However, Musashi's master, Ritsuka Fujimaru, is present, and this manages to motivate Musashi enough to win.

* In ''Webcomic/{{Homestuck}}'', Jack Noir, empowered by the Black Queen's ring (which grants him the powers of a PhysicalGod), is pursued across all of Paradox Space by [[spoiler:PM, wearing [[MirrorMatch the White Queen's ring]], hell-bent on [[RoaringRampageOfRevenge avenging her murdered friends]]]]. The chase spans the entirety of Act 6, and ends with [[spoiler:PM victorious, leaving Jack alive but [[AnArmAndALeg (literally) disarmed]]]].

[[folder:Web Original]]
* ''Wiki/SCPFoundation'': [[http://www.scp-wiki.net/roget-s-proposal Roget's Proposal]] is based on the principle of sealing dangerous [=SCPs=] using other dangerous [=SCPs=] that counter them. For example, [[http://www.scp-wiki.net/scp-140 SCP-140]] (a history book that extends itself by absorbing any writable fluid and, when no more fluid is available, retcons history to match its contents) is sealed by [[http://www.scp-wiki.net/scp-505 SCP-505]] (a pen that produces an endless quantity of ink).

[[folder:Web Video]]
* In the world of ''WebVideo/TalesFromMyDDCampaign'', the BigGood Ioun discovered the Source of all magic aeons ago. Unfortunately, the BigBad Vecna learned of the Source almost immediately thereafter, and ever since they have been locked in a duel for control of the Source. Should Vecna win, he will be able to destroy all other gods, strip all magic from the world, and rule unopposed and unopposable. To this point, Ioun holds Vecna at bay, but at any moment the end could come.
* [[InvertedTrope Inverted]] in one ''WebAnimation/DeathBattle''. The duel doesn't keep a destructive force distracted, but is instead a multiversal apocalypse unto itself. [[spoiler: Making [[MemeticBadass Chuck Norris and Segata Sanshiro]] fight each other was a very bad idea.]]
* In the final episode of ''WebVideo/CarBoys'', [[spoiler: The Blob is doomed to forever be stuck in the outer reaches of a Time Ring, chasing Nick and Griffin in their waterproof car as they remain in the Time Ring's center for all eternity, with the boys and the reality outside the Time Ring finally safe from The Blob]].

[[folder:Western Animation]]
* The 90s ''WesternAnimation/SpiderManTheAnimatedSeries''
** ComicBook/CaptainAmerica and the Red Skull. Eventually, [[spoiler:Electro joins them]].
** From the same series, a sort-of-reformed Venom ends up jumping into a portal after his EvilCounterpart, Carnage, and since the portal closes after that, it's implied that this will be their fate. A sort-of SequelSeries saw them on another planet/dimension, though.
*** The Carnage symbiote (possibly not the original) escaped at the conclusion of the original series. What happened to Kasady and Venom is never discussed.
* ''WesternAnimation/JackieChanAdventures'' ends with this, as the fifth season's BigBad Drago (using the powers of all eight demon sorcerers) and his father Shendu (the BigBad of the entire series, using all twelve of his talismans) are sealed within another realm to duel for all eternity. Neither of them takes their fate very seriously, and they spend their time bickering: Shendu chastising Drago for being an impudent child playing with his father's world (yes, Shendu still thinks Earth is his for the taking), while Drago whines about Shendu never being there for him because he's always busy fighting wizards.
* One episode of ''WesternAnimation/TheFairlyOddParents'' had a variation on this. Timmy wished [[BabysitterFromHell Vicky]] wasn't his babysitter, and she became mayor of the city instead. Subsequent attempts to remove Vicky from power through wishing instead resulted in Vicky gaining even more power, up to the point where she became a galactic conqueror. In the end, Timmy realized [[ItsUpToYou it was up to him]] to prevent any of these from happening, and wished her to be his babysitter once again.
** As for a closer example, there is an episode where Timmy wishes both of his parents were the best surfer. Due to the impossibility of two people being best at the same thing at the same time, they get locked into an eternal surfing competition known as Wish Limbo...limbo...limbo...limbo... However, it's broken when they find something that's more important to them than surfing, Timmy, who is attacked by the Kraken he wished up to try and scare them out of Wish Limbo...limbo...limbo...limbo...
* ''WesternAnimation/AdventureTime'' has Goliad, Princess Bubblegum's genetically engineered heir who'd gone mad with power and tried to take over the Candy Kingdom with her mind control powers, ultimately defeated by Stormo, another Candy Sphinx created using Finn's DNA, sacrificing himself by locking her in a psychic duel with himself. Nobody thinks to just kill or knock out Goliad now that she's incapacitated.
** In the original storyboards for "The Lich", Billy tells Finn about the Crystal Citadel, a prison for the multiverse's most dangerous criminals. He also says that Finn's birth father was unjustly imprisoned there and has been battling the criminals held there ever since.
*** This has been both confirmed and refuted in canon, as Finn's father WAS imprisoned there, but he's actually a criminal just as bad as the other inmates (so far).
* One episode of ''WesternAnimation/MightyMax'' contains this: An immortal, invincible caveman (the good guy) and an immortal, invincible sabre-toothed tiger (the villain). Originally sealed together in a cave, construction excavations accidentally freed both. Ultimately, since neither one could be destroyed, the caveman dragged the sabre-toothed tiger down to the bottom of a tarpit, where the two of them continued to battle, possibly until the end of time.
* In the season 2 finale of ''WesternAnimation/{{Wakfu}}'', this seems to be the fate of Goultard the Barbarian and Rushu, king of the Shushus, after the former drag his opponent back to his demonic realm. Indeed, the "Where Are They Now?" epilogue shows them still facing off through Igor the Shushu mirror. This is then subverted in the specials, where it's revealed that Goultard ''eventually'' (within the span of [[TimeSkip six years]]) won hands-down, and [[HellHasNewManagement is living comfortable]].
* In the backstory for ''WesternAnimation/TheLegendOfKorra'', the UltimateEvil Vaatu was kept contained by a centuries-long duel with the light spirit Raava. This fell apart when Vaatu tricked [[PrecursorHeroes Avatar Wan]] into thinking that Raava was a bully that needed to be taken down a peg.
* In the season 1 finale of ''WesternAnimation/StevenUniverse'', "Jail Break," [[spoiler:Lapis Lazuli agrees to fuse with Jasper and forms Malachite. Malachite is then dragged into the ocean by Lapis working against the fusion, and Lapis uses her water powers to create chains made out of water, effectively trapping her and Jasper in a duel at the bottom of the ocean for as long as she can survive.]]
* In the season five finale of ''WesternAnimation/MyLittlePonyFriendshipIsMagic'', [[Recap/MyLittlePonyFriendshipIsMagicS5E26TheCutieRemarkPart2 "The Cutie Re-Mark"]], Twilight Sparkle gets caught in a time loop. She warns the villain responsible for the loop that, while they're evenly matched and she can't ''beat'' her, they will keep fighting for eternity if nothing changes. The villain is [[RevengeBeforeReason perfectly fine with this possible outcome.]] [[spoiler:That is, until she sees the BadFuture it will cause with her own eyes...]]
* The ''WesternAnimation/ChalkZone'' TVMovie "The Big Blow-Up" featured a temple of Inflatermaus, a swarm of insectoid creatures that were able to infect the inhabitants of [=ChalkZone=] with a fatal disease called Balloonemia. Before Rudy Tabootie re-imprisons the swarm behind a glass wall with his magic chalk, it is revealed that [=ChalkZone=]'s long lost ruler King Mumbo Jumbo had been keeping the Inflatermaus swarm at bay all these years.