History ApocalypseHow / ClassX5

* ''Manga/{{Bokurano}}'': If you lose the game, your universe goes bye-bye. [[spoiler:If you ''win'', someone ''else's'' goes bye-bye. Provided the tournament has a standard ladder form, 2^15 - 1 universes -- ''32,767 whole universes, lifeforms included'' -- are destroyed during the anime's tenure. But hey, it may all be for a good reason... Or not.]]
* The standard effects of a Lost Logia reaching full power and going out of control in ''Anime/MagicalGirlLyricalNanoha'' are multi-dimensional catastrophes that destroy many worlds in the process.
* In ''Anime/{{Noein}}'', the goal of the title BigBad is to destroy all possible parallel universes so that only Shangri'La remains.

* ''ComicBook/DarkNightsDeathMetal'' actually ''begins'' in the aftermath of a Class X5, with only one universe left standing (an amalgamation of realities ruled by the Batman Who Laughs). Once he reaches the peak of his power, he ensures the only other worlds in the Multiverse are the corrupted, evil ones created by him ("the Last 52").
* In the Marvel Comics, [[OmnicidalManiac Unicron]] from ''Franchise/{{Transformers}}'' has this as part of his background. He ate most of the previous universe and went to sleep, only to have the scraps he left behind form a new universe while he slept. [[ApocalypseHow/ClassZ Now he wants to make sure it doesn't happen again]].

* ''ComicBook/BlackScience'': Grant unlocks pillar technology to travel to unlimited parallel worlds. Doing so leaves a trail of cracked reality back to his origin dimension. He discovers bizarre voids in the multiverse and theorizes that they are the result of traveling to an antimatter parallel universe that allowed antimatter to slide back through the cracks all the way to each pillar inventor's origin, wiping out every dimension along the way. Any dimensionaut that travels long enough will stumble into an antimatter universe and kill off everything they passed through.
* In ''ComicBook/MightyMorphinPowerRangersShatteredGrid'', this ends up being Lord Drakkon's endgame: [[spoiler:by capturing the powers of the various teams, he seeks to be strong enough to enter the Morphin' Grid and steal the Heart of a Master, destroying the Ranger multiverse and creating a universe where he's beloved by all. Thankfully, the Mighty Morphin' team, [[Series/PowerRangersTimeForce Jen]] and [[Series/PowerRangersSamurai Lauren]] are able to fix this. [[CloseEnoughTimeline Mostly]].]]

* This turns out to be the big twist in ''Series/{{Loki 2021}}'': [[spoiler:There was a multiversal war going on, presumably involving all variations of the villain Kang the Conqueror, and the last survivor, going by the name He Who Remains, created the Time Variance Authority to prune any and all deviations of the Sacred Timeline from being created so that another, possibly more crueler Kang, isn't created. This gets undone when the Loki variant known as Sylvie kills He Who Remains, causing the Sacred Timeline to erupt into many timelines.]]

* If your team is defeated in ''VideoGame/MarvelVsCapcom3'', this is the fate that ComicBook/{{Galactus}} has in mind for the Marvel and Capcom universes.
* Despite ''VisualNovel/UminekoWhenTheyCry'' being mostly a romance-mystery novel, in the final battle between [[spoiler:[[HeelFaceTurn Lambdadelta]] and Bernkastel]], both rapid-fire attacks that shatter entire fragments using the force of Big Bangs and Big Crunches. Each fragment is an entire parallel universe. On a (comparatively) lesser scale, [[GreatDetective Willard]] cuts an entire fragment in half with a single sword slice.
* While we never learn the full extent of the damage past "rampaging through timelines", it's implied that Add from ''VideoGame/{{Elsword}}'' started causing these in his Diabolic Esper path.
* The penultimate goal of [[spoiler:Airy and Ouroboros]] in ''VideoGame/BravelyDefault''. After [[spoiler:Airy uses the crystals to physically link the universes]], they'll consume the multiverse as fuel for their ''ultimate'' goal: [[spoiler:breaking into and conquering the Celestial Realm, aka ''[[TheFourthWallWillNotProtectYou the real world]]'']].
* In ''VideoGame/KirbyPlanetRobobot'', [[spoiler:shortly after achieving sentience, Star Dream declares that organic life is a liability in its goal of infinite prosperity and must be deleted. Seeing as how it later demonstrates RealityWarper tendencies and is capable of tearing holes in the fabric of space-time, it's very likely that Star Dream wouldn't stop at just Franchise/{{Kirby}}'s universe.]]
* In ''VideoGame/SuperPaperMario'', the Void is a tear in the fabric of the multiverse that will [[CessationOfExistence annihilate all worlds entirely]]. Mario has to stop it.

* This was Seargent Smacka's plan in ''Webcomic/LsEmpire''. He never gets that far, but he does succeed in causing several Class X-4s [[spoiler: which all get undone]].

* At the end of ''WesternAnimation/SpiderManTheAnimatedSeries'', Spider-Carnage, an alternate universe Peter Parker who hit the DespairEventHorizon after his universe's version of ComicBook/TheCloneSaga and was bonded with the Carnage Symbiote, attempts to destroy the multiverse, aching to a Class Z destruction (although it probably wouldn't count that far, since those sent to stop him are alternate Spider-Men, which probably means only the universes containing or related to Spider-Man would be destroyed).
* Similarly, in ''WesternAnimation/TurtlesForever'' Utrom Shredder destroys his native dimension and begins destroying another, eventually wiping out every universe that contains the Teenage Mutant Ninja Turtles.

* ''WesternAnimation/{{Futurama}}'': In one WhatIf scenario, Fry destroys almost all reality, leaving himself, UsefulNotes/AlGore, Creator/StephenHawking, [[Series/StarTrekTheOriginalSeries Nichelle Nicols]], and Creator/GaryGygax to play ''TabletopGame/DungeonsAndDragons'' for the rest of eternity.

* In ''Literature/RiddleOfTheSeven Realms'' [[spoiler:an ancient demon plots to destroy all known worlds by lighting a fire in his home dimension, which will punch a hole into the void and suck in not only the demon realm, but also all other worlds that connect to it via flames. (Presumably, any undiscovered universes that lack the "flame permeates all" rule of wizardry would escape this fate, making it this level and not Class Z.)]]

* ''Literature/MagicByTheNumbers'': ''Riddle Of The Seven Realms'' [[spoiler:an ancient demon plots to destroy all known worlds by lighting a fire in his home dimension, which will punch a hole into the void and suck in not only the demon realm, but also all other worlds that connect to it via flames. (Presumably, any undiscovered universes that lack the "flame permeates all" rule of wizardry would escape this fate, making it this level and not Class Z.)]]

* ''VideoGame/ShinMegamiTenseiIIINocturne'': though True Demon ending heavily suggests [[spoiler:Kagutsuchi's annihilation from every Vortex World at the hands of Demi-Fiend]] results in a Class Z Apocalypse, subsequent games imply the rest of multiverse is still ongoing just fine. ''VideoGame/ShinMegamiTenseiIV'' and later on ''[[VideoGame/ShinMegamiTenseiIVApocalypse Apocalypse]]'' (particularly its [[DownloadableContent DLC]], "Messiahs in the Diamond Realm" in which [[spoiler:True Demon Demi-Fiend]] appears) outright confirm the multiverse is still running and expanding.

* ''VideoGame/ShinMegamiTenseiIIINocturne'': though True Demon ending heavily suggests [[spoiler:Kagutsuchi's annihilation from every Vortex World at the hands of Demi-Fiend]] results in a Class Z Apocalypse, subsequent games imply the rest of multiverse are still ongoing just fine. ''VideoGame/ShinMegamiTenseiIV'' and later on ''[[VideoGame/ShinMegamiTenseiIVApocalypse Apocalypse]]'' (particularly its [[DownloadableContent DLC]], "Messiahs in the Diamond Realm" in which [[spoiler:True Demon Demi-Fiend]] appears) outright confirm the multiverse are still running and expanding.

* ''VideoGame/ShinMegamiTenseiIIINocturne'': though True Demon ending heavily suggests [[spoiler:Kagutsuchi's annihilation from every Vortex World at the hands of Demi-Fiend]] results in a Class Z Apocalypse, subsequent games imply the rest of multiverse are still ongoing just fine. ''VideoGame/ShinMegamiTenseiIV'' and later on ''[VideoGame/ShinMegamiTenseiIVApocalypse Apocalypse]]'' (particularly its [[DownloadableContent DLC]], "Messiahs in the Diamond Realm" in which [[spoiler:True Demon Demi-Fiend]] appears) outright confirm the multiverse are still running and expanding.

[[folder:Anime and Manga]]

* In ''Series/Dark2017'', [[spoiler: this is the fate of both Adam and Eve's universes after the StableTimeLoop is broken.]]

* This turns out to be the big twist in ''Series/{{Loki 2021}}'': {[spoiler:There was a multiversal war going on, presumably involving all variations of the villain Kang the Conqueror, and the last survivor, going by the name He Who Remains, created the Time Variance Authority to prune any and all deviations of the Sacred Timeline from being created so that another, possibly more crueler Kang, isn't created. This gets undone when the Loki variant known as Sylvie kills He Who Remains, causing the Sacred Timeline to erupt into many timelines.]]

* ''Series/DoctorWho'':
** "[[Recap/DoctorWhoS30E13JourneysEnd Journey's End]]": The Daleks threaten to cause this using their Reality Bomb. The device essentially dismantles the electrical field holding atoms together, and if it's sucessfully fired at full power in the Medusa Cascade then it will leak through the Cascade's rift into ''every single'' ParallelUniverse and AlternateDimension, so the sheltered Dalek fleet will be the only things left in ''all of reality''. It's revealed that the Reality Bomb's existence has already been causing a TimeyWimeyBall sort of WorldWreckingWave to negatively affect multiple universes and has even wiped out the Daleks and Cybermen inside the Void, although said wave's effects are stopped at the end.
** In [[Recap/DoctorWhoS31E12ThePandoricaOpens "The Pandorica Opens"]]/[[Recap/DoctorWhoS31E13TheBigBang "The Big Bang"]], after [[spoiler:the Silence detonate the TARDIS]], all that remains of every reality is that of Earth in this universe, just a stone's throw from Class Z. Stars are myths ([[spoiler:and our sun is actually the TARDIS burning]]), all that's left of non-Earth life are shadows petrified in time, and as the characters edge closer to the date of [[spoiler:the TARDIS' explosion]], people start vanishing from reality. This is reset by [[spoiler:the Doctor creating a second Big Bang with the Pandorica]]. We have a word of a Cyberman that every universe is affected. "All universes will be deleted."

* [[https://en.wikipedia.org/wiki/False_vacuum_decay False Vacuum Decay]] is a concept in quantum field theory that, if it were true, could delete the universe itself. WebAnimation/{{Kurzgesagt}} made [[https://www.youtube.com/watch?v=ijFm6DxNVyI a video]] explaining this in more detail, but in a nutshell, the Higgs field (the thing that gives particles their mass) might not be entirely stable, but metastable, and if a Higgs particle ever were to get pushed over the edge, it would collapse into a true stable state, pushing the Higgs particles around it over the edge too. This would create a bubble that expands at the speed of light, with a shell of energy around it that annihilates everything that it comes into contact with. Not just that, inside the bubble, ''physics itself'' would be turned on it head, meaning concepts like particle physics, chemistry, or atomic structures could be wildly different, or even completely impossible. Fortunately, vacuum decay is a theory based on heavily disputed evidence, and even if one or multiple death bubbles ''did'' exist, they likely wouldn't reach us for billions of years, if at all.

* In ''WebAnimation/{{Underverse}}'', Error [[spoiler: wraps is strings around the au's and destroyed almost all of them. Some people make it to the Omega Timeline.]]

* In ''WebAnimation/{{Underverse}}, Error [[spoiler: wraps is strings around the au's and destroyed almost all of them. Some people make it to the Omega Timeline.]]

* ''Series/DoctorWho'': In [[Recap/DoctorWhoS31E12ThePandoricaOpens "The Pandorica Opens"]]/[[Recap/DoctorWhoS31E13TheBigBang "The Big Bang"]], after [[spoiler:the Silence detonate the TARDIS]], all that remains of every reality is that of Earth in this universe, just a stone's throw from Class Z. Stars are myths ([[spoiler:and our sun is actually the TARDIS burning]]), all that's left of non-Earth life are shadows petrified in time, and as the characters edge closer to the date of [[spoiler:the TARDIS' explosion]], people start vanishing from reality. This is reset by [[spoiler:the Doctor creating a second Big Bang with the Pandorica]]. We have a word of a Cyberman that every universe is affected. "All universes will be deleted."

''Roleplay/DestroyTheGodmodder'': [[spoiler: Happens at the End of Act 4 in Destroy the Godmodder 2, where both Earth's universe and Minecraftia are destroyed. Earth gets restored in Act 5 - but Minecraftia [[KilledOffForReal isn't so lucky]].]]

* In the ''TabletopGame/DungeonsAndDragons'' Splat book Elder Evils, this is potentially the worst case for two scenarios:

** The villain in the Worm that Walks scenario does not intend this scale of destruction, but when its underling makes the mistake of putting a Sphere of Annihilation in a special Bag of Holding, it happens if the heroes cannot stop it.

* In ''Franchise/WonderWoman'' storyline ''ComicBook/JudgmentInInfinity'', should the heroes fail the Adjudicator's trials, he will make Earth-One fade into oblivion, triggering a chain reaction which will disintegrate all Earths in the Multiverse.

* In ''Literature/RiddleOfTheSevenRealms'' by Creator/LyndonHardy, [[spoiler:an ancient demon plots to destroy all known worlds by lighting a fire in his home dimension, which will punch a hole into the void and suck in not only the demon realm, but also all other worlds that connect to it via flames. (Presumably, any undiscovered universes that lack the "flame permeates all" rule of wizardry would escape this fate, making it this level and not Class Z.)]]

* In the MagicalGirl CrisisCrossover ''FanFic/ShatteredSkiesTheMorningLights'', [[Anime/SmilePrettyCure Joker]] unleashes [[NoNameGiven "the entity"]], a colossal [[SpaceTimeEater space-time eating]] EldritchAbomination, upon the Precure multiverse. It causes ''countless'' Class X-5s, consuming every possible future of the first ten Precure series[=/=]continuities, [[RetGone RetGone-ing]] all the ones beyond that[[note]]the ''[[Anime/MahouTsukaiPrettyCure Mahou Tsukai]]'', ''[[Anime/KiraKiraPrecureALaMode A La Mode]]'', and ''[[Anime/HugttoPrettyCure Hugtto]]'' universes are shown being destroyed before the events of their series can even begin, and [[PaintingTheMedium even the]] ''[[PaintingTheMedium text headers]]'' [[PaintingTheMedium for the "facets" after theirs begin cutting off mid-word...]][[/note]], and causing what's left to collapse together into a catastrophic TimeCrash.

* ''Series/DoctorWho'': In [[Recap/DoctorWhoS31E12ThePandoricaOpens "The Pandorica Opens"]]/[[Recap/DoctorWhoS31E13TheBigBang "The Big Bang"]], after [[spoiler:the Silence detonate the TARDIS]], all that remains of every reality is that of Earth in this universe, just a stone's throw from Class Z. Stars are myths ([[spoiler:and our sun is actually the TARDIS burning]]), all that's left of non-Earth life are shadows petrified in time, and as the characters edge closer to the date of [[spoiler:the TARDIS' explosion]], people start vanishing from reality. This is reset by [[spoiler:the Doctor creating a second Big Bang with the Pandorica]].
%% We have a word of a Cyberman that every universe is affected. "All universes will be deleted."

** The true goal of [[spoiler:Zamasu]] and Black Goku is to eliminate all of the mortals from the multiverse. [[spoiler: He succeeds in doing that in Future Trunks' timeline by becoming an omnipresent EldritchAbomination infecting that timeline's multiverse by merging his own being with it after losing his physical body (although not before both Zamasus fusing and the Merged Zamasu's intense fight against the heroes) forcing Goku to summon Zeno, who destroyed the entire multiverse in that timeline to get rid of Zamasu completely, and seeing as Zamasu slowly started to spread to other timelines, also averted a potential Class Z Omniversal FUBAR event.]]
** And once again, this time deliberately by Zeno. Whichever universe is defeated in the multiversal Tournament of Power, it gets obliterated as punishment for failure. [[spoiler:Universe 9 suffers this fate first, and Universe 10, 2, 6, 4, 3, and 11 after that leaving only five universes remaining by the end of ''Super'']]. However, [[spoiler:the Tournament of Power was just a SecretTestOfCharacter. Zeno figured there would be a mortal who would be virtuous enough to wish back all of the universes erased in the Tournament of Power, which turned out to be what Android 17 wished for. If the mortal wished for a selfish wish, which was very close to happening, Zeno would have erased not only Universe 7, but the universes that were supposedly spared in the Tournament of Power as well!]]

* ''Series/DoctorWho'': In [[Recap/DoctorWhoS31E12ThePandoricaOpens "The Pandorica Opens"]]/[[Recap/DoctorWhoS31E13TheBigBang "The Big Bang"]], after [[spoiler:the Silence detonate the TARDIS]], all that remains of every reality is that of Earth in this universe, just a stone's throw from Class Z. Stars are myths ([[spoiler:and our sun is actually the TARDIS burning]]), all that's left of non-Earth life are shadows petrified in time, and as the characters edge closer to the date of [[spoiler:the TARDIS' explosion]], people start vanishing from reality. This is reset by [[spoiler: the Doctor creating a second Big Bang with the Pandorica]].

** The world the story takes place in seems to be in the midst of planetary scale apocalypse, as all but one human are replaced by machines, and everything "fades to black".

* Despite ''VisualNovel/UminekoWhenTheyCry'' being mostly a romance-mystery novel, in the final battle between [[spoiler: [[HeelFaceTurn Lambdadelta]] and Bernkastel ]], both rapid-fire attacks that shatter entire fragments using the force of Big Bangs and Big Crunches. Each fragement is an entire parallel universe. On a (comparitively) lesser scale, [[GreatDetective Willard]] cuts an entire fragement in half with a single sword slice.

* In ''VideoGame/KirbyPlanetRobobot'', [[spoiler:shortly after achieving sentience, Star Dream declares that organic life is uncontrollable and must be deleted. Seeing as how it later demonstrates RealityWarper tendencies and is capable of tearing holes in the fabric of space-time, it's very likely that Star Dream wouldn't stop at just Franchise/{{Kirby}}'s universe.]]

* ''Franchise/TheDarkTower'': This is what happens if the Tower falls: the utter reversion of every single universe, dimension, plane, time, space etc etc. to the chaos from whence they came. The BigBad want to this because he claims he will be able to rule that chaos forever afterwards. The worrying part is that this is starting to happen already at the beginning of the series. Even more scary is that the protagonist has to succeed every single time. The antagonist just has to win once. [[spoiler: However it seems that each time it resets, the Gunslinger gets something that might make this cycle the last one where he has to win.]]

* In ''Riddle of the Seven Realms'' by Creator/LyndonHardy, [[spoiler:an ancient demon plots to destroy all known worlds by lighting a fire in his home dimension, which will punch a hole into the void and suck in not only the demon realm, but also all other worlds that connect to it via flames. (Presumably, any undiscovered universes that lack the "flame permeates all" rule of wizardry would escape this fate, making it this level and not Class Z.)]]

* ''Franchise/TheDarkTower'': This is what happens if the Tower falls: the utter reversion of every single universe, dimension, plane, time, space etc etc. to the chaos from whence they came. The BigBad want to this because he claims he will be able to rule that chaos forever afterwards. The worrying part is that this is starting to happen already at the beginning of the series. Even more scary is that protagonist has to succeed every single time. The antagonist just has to win once. [[spoiler: However it seems that each time it resets, the Gunslinger gets something that might make this cycle the last one where he has to win.]]
* In Creator/LJagiLamplighter's RachelGriffin series, universes are being destroyed. The main characters work out that some characters are in fact refugees from them, magically fit into the universe. [[spoiler:Though Rachel is warned that very few people can be rescued when a universe is destroyed.]]
* In Creator/LarryCorreia's ''Literature/TheGrimnoirChronicles'', the Power is being pursued by the Enemy that destroys the universes it attached itself to. Summoners summon the remnants of the survivors of the previous worlds.

-->--Zeno, ''Anime/DragonBallSuper''

** The firsts story of the album also begins right after an unspecified nuclear armageddon.