Sealed Evil in a Duel

aka: Sisyphus Vs Rock

Anubis: You can't kill me, either.
Oma Desala: I can fight you.
Anubis: Well, you can't win.
Oma Desala: It won't matter. You won't be able to do anything but fight me back.

— Stargate SG-1

Sometimes, the Big Bad is just too darned evil to be Sealed in a Can. Perhaps they already were, and it didn't work. After hammering them time and again, the hero eventually realizes that It's Up to Them, and carries out the Heroic Sacrifice Worse than Death: Trapping themselves in 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 using its would-be impediment as a Soul Jar.

This can also be used as a Back Story, with the release of the Big Bad also releasing the original hero.

May invoke Someone Has to Do It. On the other hand, sometimes only their conscience is keeping them on the job.

Sub-trope of Hell Is War. See also Kill Us Both; often overlaps with Enemy Without and Tailor-Made Prison. The furthest possible extension of How Much More Can He Take?. Might be the ultimate duty of a Barrier Maiden.

SPOILERS AHEAD.

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Examples:

Anime & Manga

• This may have happened at the end of ∀ Gundam. At the end of their final duel, the Turn A and the Turn X manages to inflict a Mutual Kill 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 independent will when it came to fighting the Turn A, 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. Ghingham wasn't so lucky - and since he's the pilot of the Turn X, its nanites will keep him alive indefinitely.
• Buso Renkin: The final battle between Kazuki and the Big Bad results in using the full power of his weapon to launch himself and Victor to the moon where they can fight without harming anyone until a cure for their Walking Wasteland condition can be created.
• 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 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.
• In Code Geass, it is subverted. Lelouch seals himself and the Emperor 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.
• Played with to some degree in the second season of Dog Days: 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, 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.
• Dragon Ball
  • In Dragon Ball Z, 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 Year Inside, Hour Outside Pocket Dimension 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 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.
• Four Knights of the Apocalypse: Mortlach's magic "Duelist" allows him to seal himself and anyone who accepts a duel with him into a pocket dimension, from which neither can leave until the other is killed or rendered unconscious. Additionally, magic cannot be used in this space, only pure fighting power. Inverted Trope, as Mortlach is an antagonist who uses this against the hero Percival.
• 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. 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.
• In Kenichi: The Mightiest Disciple YAMI (evil) do this to the good guys 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 a fox that Hayato considered eating but spared when he saw that it had a family distracts his opponent at a crucial moment. They don't appear to need sleep, however.
• The plot of 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 Sealed Evil in a Can. The Third Hokage later uses the same technique on Orochimaru, but didn't have the strength to get all of them, instead inflicting a Wound That Will Not Heal. This begs the question 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, 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. 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 (luckily, there are techniques that can allow them to escape) which in turn prevents them from being brought back by Impure World Resurrection.
    • The myth is eventually proved 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.
• At the end of Puella Magi Madoka Magica, 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 Informed Ability, since we never actually see this happen - 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.
• Rebuild of Evangelion: A proposed ending for 3.0 + 1.0 was Shinji and Gendo Ikari both dying physically from their final battle but their spirits still piloting their Evangelions and the mechas, at full power, continuing to wander through space forever in constant battle.
• Used in 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.
• Xam'd: Lost Memories ends with Nakiami sealing herself in the Quickening Chamber for a thousand years to offset the darkness of the Hiroken Emperor.
• Yu-Gi-Oh!:
  • Near the end of Yu-Gi-Oh! ZEXAL Yuma decides go into a stalemate with Shark because Astral World will be destroyed if he loses, but winning will mean losing his friendship with Shark. Unwilling to win or lose, he cancels his final attack and declares that he will duel Shark forever. But then it turns out that Shark had set a trap that would have caused Yuma to lose if he hadn't canceled the attack, and failing to attack causes the trap to backfire on Shark and Yuma wins anyway.
  • Yu-Gi-Oh!
    • Pharaoh Atem seals himself in the Millennium Puzzle with Zorc Necrophades. Played literally as the two of them spend the next 3,000 years jousting over the most complex RPG known to man: 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 the Abridged Series:
      Kaiba: Best. Destiny. Ever.
    • This is how the Yami defeated Marik's puppet "Strings" during the Battle City. Yami used Brain Control to hijack Strings' Revival Jam to his field. Slifer automatically destroys Revival Jam with one of its effects, causing Marik to draw three cards because of the effects of "Card of Safe Return". As its name implies, Revival Jam is revived, Silfer destroys it again, then Strings draws three more cards. The process is repeated over and over until Strings runs out of cards in his deck, resulting in his loss.

Comic Books

• Astro City: When American Chibi realizes that her presence in the real world is what allows the King-In-Chains to exert its influence beyond Ibbopolis, she volunteers to seal herself in their Pocket Dimension to keep it trapped. Chibi and the King remain locked in a never-ending battle as a result.
• Batman: An Elseworlds posits that Batman and the Joker will be fighting each other in one form or another for eternity. Batman Beyond: Return of the Joker also supports this notion, at least until Tim kills him.
• Crimson: At the end of the comic, one half of the Big Bad Duumvirate, the king of dragons, who it's implied can never be truly killed (and thus it's implied could otherwise always recreate 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 Pocket Dimension to fight each other forever. Actually subverted in that God intervened, so that the dragon king would be Fighting a Shadow for eternity, while the real Saint George, after centuries of service culminating in a Heroic Sacrifice, is finally taken to his final reward.
• Fantastic Four:
  • In one story, after Doctor Doom came within an inch of wiping out the Fantastic Four, 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.
• Godzilla:
  • An issue of the Dark Horse Godzilla comics featured Gekido-Jin, an invincible demon who is imprisoned 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 Godzilla in Hell, Godzilla finds himself trapped in a walled city replica of Tokyo i*n 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. 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.
• Judge Dredd: In the ending to "Dark Judges: Deliverance", the repentant Judge Whisper, with some help from the friendly alien Um, is able to brainwash the four other Dark Judges into believing that their brothers are about to betray them and cause them to attack each other. Since they are all immortal zombies with regenerative powers, they succeed only in wounding but never killing each other over and over again.
• Justice League of America:
  • The Shaggy Man is a mindless beast with incredible strength and seeming immortality. In its first appearance, it was finally defeated when the Flash 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.
  • In the JLA: Tower of Babel storyline, the League are up against contingencies created by Batman to incapacitate them in some way should they ever go rogue. As a proud warrior who would never give up a fight against any opponent, Wonder Woman is trapped in a simulation where she fights an opponent that's equal to her in every way, and the fight would last until she dies of exhaustion.
• Justice Society of America: The Justice Society did this when they fought the Norse Gods in Last Days of the Justice Society, to prevent Adolf Hitler from destroying the world with The Spear of Destiny. Justified as the battle was Ragnarok, which ended like this.
• Legion of Super-Heroes: During the prestige format run, the Legion finally "defeated" the Time Trapper (the Anthropomorphic Personification of the Cold Universe cosmic model) by unleashing the Infinity Man (the Anthropomorphic Personification of the Cyclical Universe cosmic model) on him. The two end up locked in eternal combat with each other.
• The Mighty Thor: After Odin got Killed Off for Real 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 they played chess for "eternity" (which lasted from the end of Fear Itself to Original Sin). To be fair this is a fairly reasonable way to keep the nigh omnipotent sky-father from breaking the story.
• Nemesis the Warlock: The final arc concludes with Nemesis stopping Torquemada from activating his "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.
• Sonic the Hedgehog (Archie Comics): While not exactly "sealed", it's revealed that the Xorda, aliens that eradicated most of the humans when Mobius was known as Earth, and 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.
• Spawn: After God and Satan, two horrible entities with a vicious Sibling Rivalry, bring about the End Times way ahead of schedule, they are left in a barren world and decide to fight each other. However, it was only a pocket dimension, as their creator, the Mother of Existence, enabled Spawn to press the Reset Button and remake Earth in his image, while banishing the two 'deities' away from it.
• Star Wars: This is how Palpatine is ultimately defeated in Star Wars Legends: Empatojayos Brand 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 Fate Worse than Death himself, fortunately, but the effort of carrying away a spirit of pure evil does cause his own spirit a great deal of suffering.
• The Transformers (Marvel): This is how the planet Cybertron and the planet-eater 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 transforming planet-sized robot.
• What If?: In Marvel Comics's what-if of their crossover Atlantis Attacks (in What If...? 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 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 Captain Universe power, which combined with his Quantum Bands to make him Set's equal. He opens the recently deceased Doctor Strange's 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, he's had time to reproduce...

Fan Works

• In the last few pages of Heartless (Drich) 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.
• Subverted in the Hunter: The Vigil fanfic 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 Nature Getting Beaten by Civilization, so it uses this trope as a power source for an empathetic attack on humanity.

Films — Live-Action

• In Doctor Strange (2016), this is how Strange convinces the godlike 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, and since time is a new and alien concept to Dormammu, Strange's plan is more than effective. Although Strange has to suffer an untold amount of deaths in the process, Dormammu eventually gets so desperately upset being trapped in the time loop that he concedes to Strange's demands in exchange for his freedom.
• One of the many alternate endings for Freddy vs. Jason had the pair locked in eternal battle in an arena in Hell.
• In Pirates of the Caribbean: The Curse of the Black Pearl, 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 Barbossa becomes mortal again.
• Used as a Back Story in The Sorcerer's Apprentice 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.

Literature

• In The Book of the Dun Cow, Mundo Cani drives the 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.
• Dungeons & Dragons: This is how the Penhaligon trilogy ends: Fain Flinn will fight Teryl Auroch forever to keep him from destroying Mystara.
• In The Golden Cat - the sequel to The Wild Road - the mentor character and the villain from the first novel are locked into this.
• In The Guardians of Childhood, Pitch was originally defeated when Nightlight speared him and trapped them both in the depths of the Earth.
• In High School Dx D 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.
• In Rick Riordan's The Red Pyramid from The Kane Chronicles, the main characters discover that the cat goddess Bast was released from an artifact that also contained 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.
• The Laundry Files (by Charles Stross): In The Rhesus Chart, a powerful vampire sorcerer attacks the Laundry and Angleton (an Eldritch Abomination Sealed Inside a Person-Shaped Can) apparently performs a Heroic Sacrifice to stop him, but they Never Found the Body 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.
• This is how Superman wins against Saturn, The Devil's Agent on Earth in the novel Miracle Monday: by threatening to spend every second of the rest of his life fighting him and undoing all his evil deeds. (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.)
• In the third Mistborn novel, Vin spends some time in this situation with Ruin after 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.
• At the end of A Night in the Lonesome October, 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 Eldritch Abomination invasion, but also confines Talbot somewhere where he can no longer harm people as a werewolf.
• In Twilight Watch from the Night Watch (Series), Anton, The Hero, 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, and 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 Dark World. 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. The Tiger ends up pulling him out to save itself, and Arina is retrieved in the following novel in order to save humanity.
    • Rather amusingly, Arina points out that facing an eternity together it won't be long before they turn to each other for, ahem, comfort. Thankfully it never comes to that.
• In the end of Pale, This is how both The Carmine Exile and The Aurum Coil end up.
• In Riddle of the Seven Realms, Astron can only stop Palodad from destroying the multiverse by pushing the Big Bad into the flame that's tearing a hole in the daemonrealm, then jumping through himself and pulling the source of flame in after him. It's subverted as Nimbia is able to create a new pocket-world within the Void to encase Astron, then retrieve him.
• This is how the Dreadking is defeated in the final volume of The Riftwar Cycle. The Dreadking is an Eldritch Abomination 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 Pug and Tomas, a human who possesses the power of a Valheru. To fully tap into that power, Tomas has to let himself be subsumed by the Valheru personality, an Above Good and Evil demigod warlord, but that's the only way he can be powerful enough to grab the Dreadking's undivided attention. So Tomas unleashes his Superpowered Evil Side, goes in to fight the Dreadking — and then Pug 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 The Sorceress from The Secrets of the Immortal Nicholas Flamel, Aoife willingly triggers this to stop Coatlicue from rampaging across the myriad worlds.
• In The Stormlight Archive, this was how the Heralds kept humanity protected from the Voidbringers. The Oathpact between the Heralds and the Shard of Honor allowed the Heralds to keep the Fused and Voidspren trapped on Braize, but the Heralds also had to go to Braize to keep the binding going. So each Desolation became a cycle: The Heralds would hide from and fight the Fused spirits until they were caught, then they would be tortured until one of them broke and released the binding, permitting the Fused to return to Roshar and start another Desolation.
• A variant in the Dr. Seuss 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.

Live-Action TV

• Doctor Who:
  • This was one of the proposed endings for "The Trial of a Time Lord": The Doctor and the Valeyard would have been lost somewhere in the Matrix, fighting for all eternity. If the series got renewed, the Doctor could be said to have escaped. If the series did not get renewed, well...
  • 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. 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.
    The Doctor: They went off to fight a bigger war. The Time War.
    Jack: I thought that was just a legend.
    The Doctor: I was there. The war between the Daleks and the Time Lords, with the whole of creation at stake.
  • A nod to this trope is seen in "Last of the Time Lords". After the decisive defeat of The Master, the Doctor is not willing to execute the only other member of his species in existence. So he volunteers to live up to this trope, keeping the Master confined in the TARDIS for all eternity or until he reformed. The Master prevents this by committing suicide (or at least refusing to come back from the dead).
  • 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 lifetime of the universe. The Doctor nearly did it himself, but had a More Expendable Than You pulled on him.
• Stargate SG-1: 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", a.k.a. Anubis.
  • It occurs again at the end of Stargate: 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. Morgan LeFay engages her in combat to take her out permanently.
• Star Trek: The Original Series: In the episode "The Alternative Factor", the sane Lazarus asks Captain Kirk to imprison him and his 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. Fridge Logic 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.
• Star Trek: Deep Space Nine combines this with Sealed Evil in a Can when an alien race sends two warring factions to a desolate moon. While it's unlikely that they would be able to escape even if they did stop fighting each other long enough to try, they never even attempt to stop fighting.
• In the season 5 finale of Supernatural, "Swan Song", Sam invites 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. Sam does end up jumping into the cage, with Michael (in Adam) falling in with him.
• Super Sentai
  • In the final episode of Kikai Sentai Zenkaiger has Kaito end up locked in a mental battle with the creator of worlds to decide the fate of the multiverse. The two of them can't actually defeat each other and so they decide to settle the battle with Rock Paper Scissors so that they won't end up fighting each other forever.
  • In one episode of Avataro Sentai Donbrothers, the Donbrothers accidentally unleash an unstoppable android called Donkiller that was intended to destroy the Donbrothers if they ever went rogue. Jiro then accidentally unleashed a second android called Donkillerkiller that was made to fight Donkiller. The two are completely evenly matched and are shown continuing their battle in space with no winner.
• Van Helsing (2016): It's eventually revealed that centuries ago, Abraham Van Helsing sealed away the Dark One in a shadow realm, but had to let himself be trapped there as well to ensure it happened. When she escapes in the Season 4 episode "Metamorphosis", Vanessa repeats Abraham's actions, tackling the Dark One back through the portal, which closes behind them.

Mythology and Religion

• One of the alternate names for this trope is "Sisyphus vs Rock", and is based off the myth of King Sisyphus. This man was very clever, enough so that he managed to escape Tartarus twice. When he finally died a third time, Hades had enough of his trickery and was done trying to take chances with him. So he forced Sisyphus to roll a large boulder up a hill, while also ensuring the boulder would never reach the top and roll right back down whenever he got close. Some versions of the myth suggest Sisyphus could stop at any time he wanted, but he is so fueled by his arrogance and pride that he refuses to accept defeat.

Tabletop Games

• This is the origin of the Calim desert in the Forgotten Realms Dungeons & Dragons setting, in the form of a never-ending duel between a djinn and efreet lord.
• In the 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.
• Legend of the Five Rings does this with Hida and his son, and later with Iuchi Karasu and Kuni Yori.
• In Magic: The Gathering'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.
• Sisyphus shows up in the Fantasy Kitchen Sink that is 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 Nigh-Invulnerable, 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...)
• Warhammer 40,000
  • 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 Fate Worse than Death; the Orks consider this paradise.
  • An absolutely massive version of this exists in the Octarius War between the Orks and Tyranids. As Hive Fleet Leviathan began to close in on Terra, Inquisitor Kryptman managed to steer the fleet into the Ork empire of Octaruis, causing the two sides to begin fighting with each other. While the Tyranids have managed to deal a decisive blow to the P Ork forces, fighting is still ongoing and it's expected that whichever side emerges from the conflict will be a force to be reckoned with.
• On the 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.
• A spell card called Different Dimension Gate emulates this trope in the Yu-Gi-Oh! 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.)

Video Games

• Shurelia's Heroic Sacrifice in Ar tonelico: Melody of Elemia, to seal the Big Bad Mir. You get the chance to defy this. If you do, both Shurelia and Mir get better.
• In Peketo's ending in The Black Heart, 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 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.
• In the backstory to 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 Badass Longcoat 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. Also, he was a time-travelling Ragna with amnesia, meaning Ragna unknowingly took his title from himself.
• Blizzard Entertainment likes this trope.
  • It begins in Diablo. This is what the protagonist attempts after slaying Diablo's current avatar. Needless to say, it didn't work.
  • In 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 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 in an attempt to rescue Tal Rasha.
    Tyrael: No! Don't do it!
    (pop goes the soulstone)
    Tyrael: Fool! You have just ensured the doom of this world!
  • In World of Warcraft, 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.
  • At the end of World of Warcraft: Legion Big Bad Sargeras is dragged to the Seat of the Pantheon by the rest of the Titans. With the assistance of Illidan, the Titans are now locked in a struggle with Sargeras to prevent his release.
• Towards the end of Breath of Fire II, 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 Hell Gate closed and prevent the release of Death Evan. Slightly subverted in that you must relieve her of this task by going through the Hell Gate and defeating the Big Bad. If you choose not to, Death Evan eventually overwhelms her defenses and bursts to the surface, resulting in a Nonstandard Game Over.
  • Even after Death Evan is defeated, demon gods don't just die, so the Hell Gate 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? Turns out that a giant airship works just as well as a giant dragon for sealing a hole.
• In Castlevania: Symphony of the Night, 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).
• In one of the books based on City of Heroes, Statesman and Lord Recluse compare themselves to Sisyphus and the rock. Statesman wonders which one is which...
• Doom 64: 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. Doom Eternal deconstructs this as fighting against demons in Hell for a long time eventually wore away at Doomguy's sanity, and he was a madly raving wreck by the time the Night Sentinels found him.
• Dragon Age: Inquisition: In "The Jaws of Hakkon" DLC, it is eventually revealed that the last commander of the original Inquisition, Inquisitor Ameridan, who disappeared a thousand years ago, has actually been frozen in time in a remove Frostback Basic cave, after challenging the semi-divine evil dragon named Hakkon to a duel, realizing that Hakkon is too strong for him, and stopping time around them until someone, hopefully, comes to his aid. That someone is, of course, the Inquisitor, though because Ameridan has been trapped in time for so long, he dies almost immediately after being released, leaving the Inquisitor to finish the fight on their own.
• For the very last fight of Duel Savior Destiny Taiga decides to invoke this one against 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. Still, he manages to put a seal over God eventually, letting him return home.
• The Elder Scrolls V: Skyrim:
  • After inadvertently waking the Dragon Priest, Morokei, in the depths of Labyrinthian, 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.
• As described by Noah Antwiler, ET The Extraterrestrial on the Atari 2600 vs. the Player is pretty much this.
• Fate/Grand Order: In the Shimosa Province event, this briefly happens when Miyamoto Musashi and Sasaki Kojiro 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 Yin-Yang Clash creates a Reality-Breaking Paradox 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.
• Final Fantasy
  • The Warring Triad in Final Fantasy VI 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 Kefka moving the statues out of alignment that caused their magic to lose control, causing The End of the World as We Know It.
  • Eldritch Abomination Sin in Final Fantasy X is the result of the most powerful Summon Magic that defeated Sin itself (the Final Aeon) becoming the "host" to Yu Yevon. That Final Aeon's original being (at the time of the game is protagonist Tidus' Disappeared Dad Jecht, although it's implied other previous hosts have attempted) tries to wrest control from Yu Yevon, to middling success. Jecht at least manages to exert some control, like calming down when Jecht hears his favorite song, or preventing Yu Yevon from directly harming his son.
• Freedom Force vs. The Third Reich: Manbot and the Wraiths of Chaos.
• This can be turned to your advantage in FTL: Faster Than Light, where if you have shields too powerful for the enemy to pierce (and they don't have missiles), you can choose not to attack and let your ship endlessly block or dodge their shots, with each block or dodge levelling up your crew a little bit. If you also have a weak weapon like the damageless Ion Cannon, you can also blast away at them for no damage, levelling up your weapons at the same time. Let the game idle for a few minutes and your crew will be maxed out in no time.
• Kingdom Hearts: Birth by Sleep 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 Terra-Xehanort splits in two, his Heart becoming False Ansem and his Body becoming Xemnas; what they've been doing since then is anyone's guess.
  • Kingdom Hearts 3D [Dream Drop Distance] indicates that both Ansem and Xemnas know about Master Xehanort, and their defeat recreated both Master Xehanort and Terra-Xehanort. Kingdom Hearts III reveals that Ansem's Guardian is Terra's Heartless.
• The backstory of Renekton and Xerath from League of Legends: Renekton and his brother Nasus where Ascended warriors of the ancient empire of Shurima, granting them incredible power and immortal lifespans. Xerath, however, stole his own form of Ascension more powerful than their own, killing the emperor in the process. Realising that even together they couldn't defeat him, Renekton dragged Xerath into a tomb and told Nasus to seal them both in forever. The lore mentions that Renekton and Xerath fought for centuries in the tomb, but over time Xerath got inside Renekton's head and convinced him that actually Nasus was the enemy who sealed him in on purpose as the millennia eroded his sanity. This caused a problem when they were released by a pair of tomb raiders in the present day.
• The Legend of Zelda:
  • In The Legend of Zelda: Skyward Sword:
    • Zelda, after traveling into the past shortly after Hylia's battle with Demise, voluntarily seals herself in a crystal to maintain the seal imprisoning him. Her slumber in the crystal lasts thousands of years until the present day, when she finally awakens after Link destroys Demise for good.
    • The Master Sword, the iconic weapon of the series, is this. The sword's spirit Fi takes it upon herself to seal Demise's soul within herself. Demise manages one last parting shot by placing a curse on Link and Zelda that dooms them to face an incarnation of his hatred whenever they are reincarnated. That incarnation turns out to be the series Big Bad Ganon.
  • In The Legend of Zelda: Breath of the Wild, the only reason why Calamity Ganon hasn't completely destroyed Hyrule already is because Princess Zelda has been busy keeping him sealed inside Hyrule Castle for the past 100 years.
  • Likewise, in The Legend of Zelda: Tears of the Kingdom, Ganondorf was incapable of conquering and/or destroying Hyrule for eons because King Rauru had been sealing him in the Depths all that time. Unfortunately for Link and Zelda, their discovery of Ganondorf's dessicated body occurs mere seconds before Rauru's disembodied right arm falls off and the seal is broken.
• In Lost Odyssey, this is the fate Gongora wanted to avoid, cue the 30 years long Evil Plan. Of course, in the end, making 4 powerfull immortals very pissed backfire at the end.
• Mega Man Battle Network 6: Cybeast Gregar and Cybeast Falzar 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).
• An unintentional and non-heroic example happens in Middle-earth: Shadow of War. Sauron barely manages to avoid being defeated by absorbing Celebrimbor's spirit, but in ends up with both their spirits fighting for control over the Eye of Sauron for a very long time. But also, the fact that Celebrimbor now wants to take Sauron's place makes this more of a Sealed Evils in a Duel. This ends up working against Sauron in the end, as it impaired Sauron's ability to invade the rest of Middle-Earth. Talion himself does this by plunging Mordor into a state of constant warfare to occupy Sauron between the timeframe of The Hobbit and The Lord of the Rings.
  Elthariel: Sometimes, stalemate is victory.
• Pokémon:
  • In Pokémon Ruby and Sapphire, Wobbuffet was given the ability Shadow Tag, which prevents its opponent from leaving the battle (both via fleeing and via switching out). This inadvertently caused this trope to become possible: Wobbuffet's attacks all involve its opponent attacking and Wobbuffet hitting it even harder in retaliation (and fail if the opponent does no damage), so a battle between two Wobbuffet lasts until they run out times they can use their moves and are forced to use Struggle, since they can't leave and are eternally waiting for the other to strike. However, the item Leftovers heals the Wobbuffet a small amount every turn if the Wobbuffet holds it, and since it heals more damage than Struggle causes, having two Wobbuffet fight each other one-on-one while holding Leftovers results in an endless battle, causing Wobbuffet to become the first non-legendary Pokémon to be banned from official tournaments. This was fixed in Pokémon Diamond and Pearl, where Shadow Tag doesn't work if the opponent also has Shadow Tag, and Struggle does 1/4 of maximum HP in damage with recoil.
    • The in-game dex entries even reference this, saying that when two Wobbuffet meet they'll engage in tests of endurance where they'll go days without eating or sleeping until one of them falls.
  • The infamous "Funbro" 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 ^*While keeping the opponent alive is mainly just to troll, it does technically have competitive merit by denying the opponent the ability to ever send in a different, more powerful Pokémon. 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.
• Quest for Glory IV has this with Erana and Avoozl. Ultimately, the hero's reason for being summoned is to finish summoning Avoozl, breaking the stalemate in favor of the Eldritch Abomination, only to free Erana who, now unbound, can banish Avoozl properly.
• RuneScape: Seren intended to inflict this on the armies battling the forces of the elder gods in Sentisten by using an artifact called the Eye of Het to endlessly resurrect them, and thus make sure that they could continue fighting to keep the Elder Gods from reclaiming their stollen eggs indefinitely. Zamorak however figured out what she was planning to do and destroyed the artifact and abandoned the battle, deciding he would rather he and his armies be free even though this would doom the universe.
• Blue's ending in SaGa Frontier 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. Word of God says he teleported out, but that's not nearly as cool...
• In the backstory of Sakura Wars (2019), the Imperial, Paris and New York Combat Revues fought in the Great Demon War. With Hinata Amamiya's Heroic Sacrifice, the Revues sealed themselves to stop the demonic threat for good.
• Soul Sacrifice 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 Magusar, each with a different format. At the end of the writer's journal, 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 present host fights both against him, but in the ''Delta'' expansion, also the 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 Star Wars Legends, Jedi Master 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 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. Killing Hoth and numerous other Jedi was just a bonus, and they would be dead regardless of the initial fight's result.
• Calypso's ending in Twisted Metal 4 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...
• The cancelled Ultima X: Odyssey: When The Avatar sealed himself and his Enemy Without, 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 The Power of Friendship backing them up.
• In Undertale's most evil ending, Sans gets into a battle with the Fallen Child, a.k.a. the player character. Sans knows he can't possibly win, but he also knows that battles in the game use turns. So, near the end of the battle, after everything else he's tried has failed to kill his opponent, he decides to pull out his ultimate move: doing absolutely nothing. If he never attacks, he never ends his turn, and his opponent's turn will never come, therefore trapping the two of them in the battle until the end of time. Unfortunately for Sans, Surprisingly Realistic Outcome when his Brilliant, but Lazy 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.

Webcomics

• In Homestuck, Jack Noir, empowered by the Black Queen's ring (which grants him the powers of a Physical God), is pursued across all of Paradox Space by PM, wearing the White Queen's ring, hell-bent on avenging her murdered friends. The chase spans the entirety of Act 6, and ends with PM victorious, leaving Jack alive but costing An Arm and a Leg (literally).

Web Original

• Fine Structure has two eldritch entities from much higher dimensions dumped into our universe, because one of them was a superweapon and this was seen as the only way to stop it, and it was too strong to be battled in their higher-dimension home world.
• SCP Foundation:
  • Roget's Proposal is based on the principle of sealing dangerous SCPs using other dangerous SCPs that counter them. For example, 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 SCP-505 (a pen that produces an endless quantity of ink).
  • SCP-1959 is a Soviet cosmonaut who's been trapped alone in Earth's orbit since The '70s but is unable to die. According to one story, he's been possessed by an Eldritch Abomination and is constantly fighting to keep it in orbit with him rather than let it lay waste to Earth below.
  • SCP-3999 was a reality-warping Eldritch Abomination who ended up trapping itself and a Foundation researcher in a Pocket Dimension, inflicting Cruel And Unusual Deaths before resurrecting him to do it all over again for millions of years. Despite this he never allowed it to break his spirit, and somehow managed to end the stalemate with a Taking You with Me before it could extend its influence to others.

Web Videos

• In the final episode of Car Boys, 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.
• Inverted in one DEATH BATTLE!. The duel doesn't keep a destructive force distracted, but is instead a multiversal apocalypse unto itself. Making Chuck Norris and Segata Sanshiro fight each other was a very bad idea.
• In the world of Tales From My D&D Campaign, the Big Good Ioun discovered the Source of all magic aeons ago. Unfortunately, the Big Bad 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.

Western Animation

• Adventure Time 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. The duo can be seen in the background of some shots for the rest of the series.
• The ChalkZone TV Movie "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.
• The Fairly OddParents!:
  • One episode had a variation on this. Timmy wished 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 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...
• Jackie Chan Adventures ends with this, as the fifth season's Big Bad Drago (using the powers of all eight demon sorcerers) and his father Shendu (the Big Bad 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.
• Justice League Dark: Apokolips War ends this way. Raven and Constantine of all people come up with the plan to defeat Darkseid once and for all by releasing Raven's demon father Trigon from his mystical prison inside her mind. Cyborg, in his Dying Moment of Awesome, traps planet Apokolips—along with Darkseid and Trigon—in the empty void between dimensions where they can battle it out for all eternity. The kicker? Trigon is completely ecstatic to finally have a Worthy Opponent and tells the remaining heroes, "Go, unless you would fight me for the right to destroy him." He also thanks his daughter for such a thoughtful "parting gift."
• In the backstory for The Legend of Korra, the God of Evil Vaatu was kept contained by a centuries-long duel with the light spirit Raava. This fell apart when Vaatu tricked Avatar Wan into thinking that Raava was a bully that needed to be taken down a peg.
• One episode of Mighty Max 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.
• My Little Pony: Friendship Is Magic:
  • The season five finale "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 perfectly fine with this possible outcome. That is, until she sees the Bad Future it will cause with her own eyes...
  • In the season seven finale, "Shadow Play", Twilight Sparkle discovers that Starswirl and Pillars sealed themselves in Limbo to contain the Pony of Shadows. She decides it's a great to let them out. Reasoning that Equestria would be safer with Starswirl and the Pillars back in it. Unfortunately, she also releases the Pony of Shadows. Yeah...Oops.
• The 90s Spider-Man: The Animated Series
  • Captain America and the Red Skull found themselves trapped in an energy vortex while in the middle of a battle. They are freed, but Cap later pulls Red Skull back into the vortex, so they find themselves in the same situation as before. Eventually, Electro is thrown into the vortex as well.
  • From the same series, a sort-of-reformed Venom ends up jumping into a portal along with his Evil Counterpart, Carnage, and since the portal closes after that, it's implied that this will be their fate. A sort-of Sequel Series 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.
• In the series finale of Star Wars Rebels, Ezra recruits purrgil to hyperspace Thrawn somewhere far away, and then goes with him to make sure that he stays there. Unlike most examples, he has no intention of keeping this up forever and leaves a message for his family to come and find him when the Empire is defeated and Thrawn is no longer a threat.
• In the season 1 finale of Steven Universe, "Jail Break," 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. Subverted later on when Jasper manages to come out the victor enough to force Malachite back to the surface and break loose of the chains (along with Malachite's own will gaining some level of control), though shortly after this Malachite fought the Crystal Gems and was forced to defuse back into her components.
• Tigtone: In one episode, Tigtone and his female counterpart Beconka both sell a fragment of their souls to a giant in exchange for enchanting their weapons. The giant places their soul fragments into the same pocket so the two of them can fight each other for eternity.
• In the season 2 finale of 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 six years) won hands-down, and is living comfortable.
• The Season 1 finale of What If…? (2021) ends with Zola and Killmonger locked in a telekinetic battle over the Infinity Stones, at which point Strange Supreme and Uatu resort to locking them in a tiny pocket dimension with Strange vowing to watch over it for eternity. Unusually, in this case both members of the duel are evil, fighting for ultimate power.

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