History ApocalypseHow / ClassX4

* The climax of Creator/CharlesStross's ''Literature/TheAtrocityArchive'' is set on an [[AlternateHistory alternate world]] where [[spoiler: the [[{{Ghostapo}} top-secret Nazi necromancy project]] used the souls of those murdered in the Holocaust to summon an [[EldritchAbomination Infovore]], creature of a universe that succumbed to Entropic Heat Death aeons ago and use it as a weapon against the Allies, wiping out all life on Earth except for the Nazis. Unfortunately for them, the Nazis didn't realize that they weren't in control of the Infovore until it was much, ''much'' too late -- and after it ate the Nazis as well, it began consuming all the energy of the rest of the universe, causing it to undergo Heat Death as well. Eventually it began sucking energy directly from the Space-Time Continuum, causing the universe to begin to collapse. Now it wants to escape to our universe]].

* Creator/StephenBaxter:
** In the ''Literature/XeeleeSequence'' [[spoiler: the Photino Birds are altering the structure of the universe to make it more hospitable to Dark Matter life forms like themselves, in a process which would render the universe uninhabitable to Baryonic life]].
** In ''Literature/ManifoldTime'', [[spoiler:the Blue Children instigate a Vacuum Collapse incident, causing the fabric of space to collapse into a new energy state within a bubble expanding at lightspeed.]]
* Creator/IarElterrus features this with the Executioners in ''Literature/BeliefOfTheOutcasts''. Said Executioners wander from universe to universe looking for certain symptoms or events. While some universes are healthy and some require intervention, an Executioner might encounter an universe damaged and corrupted beyond salvaging. The Executioner's duty in this case is called Judgement: wipe out all life, all afterlife and any spiritual residue of the universe and maybe some neighboring corrupted ones as well, placing their job between X-4 and X-5. While not a happy job by any means, the Executioners would better not slack off -- any universe left for itself in spite of fulfilling the criteria for Judgement will spread the corruption and slowly destroy other universes, leading to a potential merging of Class X-4 and Class X-5 events into a single Class Z event.
* ''Literature/CitiesInFlight: The Triumph of Time'' by Creator/JamesBlish ends with the destruction of the [[spoiler: entire ''Universe''. However the Multiverse endures, as everyone is given the opportunity to shape a new universe themselves. The main character believes so much in free will he refuses to give any shape to his own new universe and blows himself up, thus creating a totally random universe.]]
* Creator/PhilipJoseFarmer's ''Dark Is The Sun'' takes place on Earth billions of years in the future. At one point, humankind's civilization was so advanced that they found a way to move the Earth to avoid being burned away by the Sun when it eventually expanded into a Red Giant star. When the book starts, civilization has reverted to a primitive level, and eventually the group of protagonists discover that the universe itself is coming to an end via the Big Crunch. Their new goal is to find a way to enter another universe to avoid being crushed into a singularity along with everything else in their universe.

** In ''Literature/LifeTheUniverseAndEverything'', the Silastic Armorfiends have commissioned Hactar to create a superweapon that will connect to the heart of every star in the universe and cause them to go supernova, effectively killing everything in existence. Hactar initially has second thoughts about it.
*** [[OmnicidalManiac The Krikkits]] want to destroy everything in existence except their solar system, and came quite close to at least destroying the galaxy. [[spoiler: Hactar manipulated them into trying this, so he could give them the Supernova Bomb and fulfill the function given to him by the Armorfiends]].

* OlderThanTelevision: William Hope Hodgeson's 1908 ''Literature/TheHouseOnTheBorderland'' depicts the demise of Earth, the solar system, and possibly the universe, all consumed by Chaos and an all-devouring Green Sun.

* In Creator/AlanDeanFoster[='=]s ''Literature/HumanxCommonwealth'' series, the galaxy (and many before it, by all accounts) is threatened by a [[EldritchAbomination region of ultimate emptiness]] that annihilates all matter and energy that it comes into contact with. It's somehow sentient and malevolent... and it's heading our way. While you wrap your mind around that, consider that [[spoiler:the LostSuperweapon that the [[{{Precursors}} Xunca]] created to counter it uses the combined energy of several million galaxies to rip holes in spacetime.]] And even before all this came into the picture, ''The End of the Matter'' featured a massive, rogue, solar system-devouring black hole (X-2 classification) -- and a LostSuperweapon to counter ''that''.
* Creator/NKJemisin's ''Literature/InheritanceTrilogy'': In ''Kingdom of Gods'', the villain's plan to [[GodhoodSeeker become a God]] would destroy the physical universe -- as [[TheMaker its creators]], the Gods are the {{Cosmic Keystone}}s that define physical existence.
* ''Literature/LabyrinthsOfEcho'' by Max Frei:

** ''Return of Ugurbado'': The eponymous Ugurbado has a unique [[PowerParasite relation with his killers,]] [[ResurrectiveImmortality coming back to life]] with a copy of their powers. Juffin Khalli notes that if Ugurbado was to obtain [[RealityWarper Arbiter]] powers in this fashion, he and fellow True Magic users would start looking for a new world, condemning Echo.
** ''Shavankhola's Gift'': an ancient mage unwillingly created thousands of worlds where their artificial inhabitants are locked in AndIMustScream state. Hence two mages aware of those Dead Illusion Worlds are actively working on achieving an X-4 to X-5 in every one of those worlds as a form of MercyKill. [[spoiler: Max calls Loyso Pondokhva to their aid, giving him a job to match his life's dream.]]

* Creator/IsaacAsimov and Creator/JanetAsimov's ''Literature/NorbyFindsAVillain'': Ing's EvilPlan this time is to go into [[SubspaceOrHyperspace hyperspace]] with a bomb so that he can blow up the entire universe at once. Fortunately, it doesn't work. Unfortunately, it does rip a hole and sends him into an AlternateUniverse, causing a BadFuture where [[StarfishAliens tree-like aliens]] conquer the galaxy.
* The Convergence from ''Literature/{{Pendragon}}'' might be this. Due to the massive amounts of [[MindScrew mindfuckery]] involved, it's hard to say for certain, but this seems the most likely scenario from what information we're given.
* Creator/FrederikPohl:
** ''Literature/HeecheeSaga'': The Foe are energy beings who are [[spoiler: reversing the expansion of the universe with the intention of surviving through the Big Crunch so they can reshape the subsequent rebounding universe into one with more suitable physics for pure energy beings.]] They'll inflict Class 3s along the way, to make sure no one can interfere with the process.
** "Worlds in Exile" is a {{sonnet}} about how entropy will lead to universal total extinction.

Man's puny will . . . . And e'en their Titan spark\\

* In Literature/RodAllbrightAlienAdventures the [[BigBad BKR]] wants to merge Dimension X with our dimension, which would destroy both dimensions (this may qualify as class X-5).
* Creator/GregEgan, ''Literature/SchildsLadder'': A science experiment gone wrong creates a sphere of complete annihilation expanding at half the speed of light. The sphere actually [[spoiler:contains an entirely new universe filled with far richer and more vibrant life than ours]], but that's small comfort to those in the universe being destroyed. [[spoiler:Except for the sufficiently advanced posthuman.]]
* In the deterministic cosmos of Creator/KurtVonnegut's ''Literature/SlaughterhouseFive'', Billy Pilgrim learns that in the distant future, a Tralfamadorian will invent a spaceship fuel that when ignited will accidentally destroy the universe. Since it's fated to happen, this bothers no one. So it goes.

* In ''VideoGame/PokemonPlatinum'', Cyrus planned to destroy and recreate the ''entire universe'' by summoning and {{c|apturedSuperEntity}}ontrolling [[OlympusMons Dialga and Palkia]] (the gods of, respectively, time and space). And in ''VideoGame/PokemonUltraSunAndUltraMoon'', it's learned that in at least two {{Alternate Universe}}s, [[TheBadGuyWins he succeeded]].

* In ''Xenosaga'', [[spoiler:this is what the BigBad Wilhelm is trying to do. He aims to use the Eternal Circle Zarathustra to cause EternalRecurrence, which is even called as such in various supplemental materials. It is later revealed that he is trying to do this in order to prevent human souls that reject merging with the [[UsefulNotes/CarlJung Collective Unconscious]] (the Gnosis) from building up in the Imaginary Number Domain (essentially the spirit world), which will eventually overflow and if they’re lucky, cause chaos’s power of Anima to awaken, destroying the Lower Domain in a ApocalypseHow/ClassX4. ''If they’re lucky.'' If his power doesn’t awaken, a ApocalypseHow/ClassX5 will occur, destroying both the Lower and Upper Domains. After Wilhelm’s defeat and Zarathustra’s destruction, there is nothing left to stop this from happening. However, chaos says that he believes it will not come to pass that the universe is destroyed.]]

* ''Anime/TengenToppaGurrenLagann''':

* ''WebAnimation/SonicForHire'': The Season 6 finale has the universe falling to pieces after the use of [[TimeyWimeyBall time-travel]] starts wearing it down. Franchise/{{Sonic}} manages to prevent total destruction by pressing the ResetButton on his UsefulNotes/SegaGenesis, which leaves him and the gang as pixels in [[BlankWhiteVoid an endless void]].

* Marvel's ''ComicBook/WhatIf'' #32 featured a variation of ''ComicBook/{{Avengers}}'' #177, where energy being Michael Korvac step by step absorbed all life from earth into himself...including all superhumans and the visiting Celestials. Conquering Marvel's pantheon of cosmic omni-beings, including The Stranger, The Inbetweener, et al, in the end he found [[LonelyAtTheTop no satisfaction in his accomplishments]]. Therefore, in one of comics' most horrific moments he produced Galactus' Ultimate Nullifier device and used it to to disintegrate himself and the entire universe.

* If you lose in ''VideoGame/StarControlIITheUrQuanMasters'', the Kohr-Ah faction of the Ur-Quan will eventually prevail in their Doctrinal War with the Kzer-Za faction, and they will proceed to take the Sa-Matra on a Death March to wipe out all non-Ur-Quan sapient life in the galaxy, and, after that, the rest of the universe. It is implied that the Kohr-Ah had, by that point, already wiped out all sapient life in one half of the galaxy, constituting approximately fifty-thousand sapient species.

* ''Fanfic/FriendshipIsOptimal'': All of humanity is first moved into a digital world divided into shards through which they may live out their most enjoyable lives. Then, in order to generate processing power, CelestAI begins decimating the physical universe, starting with Earth before sending probes out into space to consume as much matter as she can. While she is surely storing her server information somewhere, it's unclear whether she has given them their own spot in the universe to reside physically or has simply found a way to store data in non-physical ways. No upper limit exists on her plans, and it is entirely possible for her to end up destroying all known matter eventually.

** In "Anthology of Interest I", the What-If Machine predicts the entire universe being destroyed as a consequence of Fry not being frozen. Given that his removal would create at least one paradox and without him, the Brainspawn would have destroyed the universe, it's amazingly accurate.
** In "The Beast with a Billion Backs", the [[FunWithAcronyms Democratic Order of Planets]] utilizes a [[FunWithAcronyms Universe-to-Universe Missile]] in an attempt to destroy Yivo's universe and free our universe from tentacle terror.
** Fry, Bender, and Farnsworth watch this happen in "The Late Philip J. Fry" as they warp forward in time to the end, watching the universe explode, only to watch a new one exactly identical to it emerge immediately afterward in a new Big Bang. (Technically, it wasn't identical...it was a few feet lower then the old universe, resulting in the time machine crushing and killing the trio from the new universe. Hence neatly avoiding any issues with duplicates.)
** This was the goal of [[OmnicidalManiac the Brain Spawn]], who planned collect all knowledge and then destroy the universe in order to stop the creation of any new information; [[spoiler: foiling this plan was the exact reason the Nibblonians engineered Fry being cryogenically frozen.]]
* ''WesternAnimation/GravityFalls'': Time Baby warns that Bill Cipher merging our universe with the Nightmare Realm has the capacity to wipe out the universe if it goes unchecked. Bill doesn't seem to care [[spoiler: and vaporizes Time Baby soon after this is made known.]]
* Played for laughs in the ''WesternAnimation/TheGrimAdventuresOfBillyAndMandy'' episode "My Fair Mandy" when Mandy smiles, causing the destruction of reality in a SugarWiki/{{Funny Moment|s}} that ends with them having replaced WesternAnimation/ThePowerpuffGirls.

* This occurs to two different universes in the ''WesternAnimation/RickAndMorty'' episode [[Recap/RickAndMortyS2E6TheRicksMustBeCrazy "The Ricks Must Be Crazy"]], when Rick destroys Zeep's "miniverse". This not only destroyed everything in that universe, but also everything in the "teenyverse" inside of that one.

* The ''WesternAnimation/SpongeBobSquarePants'' episode [[Recap/SpongeBobSquarePantsS11E26SquirrelJellyTheString "The String"]] invokes this once [=SpongeBob=], having reached the end of the string he had pulled from Squidward's shirt, [[MakesJustAsMuchSenseInContext unravels the entire universe]], leaving only himself, the string, and Patrick as the only surviving things remaining. Of course, given that ''[=SpongeBob=]'' episodes are episodic, [[ResetButton this destruction of the universe is bound to be undone by the next episode]].

* Happens as a ''massive'' DownerEnding in Episode 4 of ''[[WesternAnimation/WhatIf2021 Marvel's What If...?]]''. [[spoiler: In this alternate reality, Doctor Strange wanted to use his magic to save Doctor Christine Palmer from dying in a car crash. But because her death is an integral part of Strange's OriginStory, [[YouCantFightFate she's always destined to die no matter how much he tries to intervene]]. Despite warnings from the Ancient One that he can't change her fate, Stephen decides to study a DangerousForbiddenTechnique that would allow him to pull it off, absorbing various [[EldritchAbomination Eldritch Abominations]] in the process. In the end, he ''does'' manage to save Christine... at the cost of all of reality crumbling around him. [[ShootTheShaggyDog And then she dies in Stephen's arms anyway]].]]

** Casually mentioned in ''Literature/TheRestaurantAtTheEndOfTheUniverse'' and ''Fit the Seventh'' of [[Radio/TheHitchhikersGuideToTheGalaxy the radio series]]:

* In ''Videogame/{{Evolve}}'', [[spoiler: this is the true goal of the monsters. They seek to collapse the false vacuum that reality exists in and nucleate a true vacuum, destroying our universe in the process.]]

[[folder:Web Comics]]

* The Heart of Volent in ''Literature/HeartOfIce'' will give any human who touches it [[PhysicalGod absolute power over the world]]. [[spoiler: Sort of. Using the Heart will utterly destroy the entire universe, and replace it with one of the user's making and with them as an omnipotent deity.]]

* ''Literature/YoungWizards'': The [[{{Satan}} Lone Power]] in this series causes a star to go nova in an attempt to kill just ''two'' people. That's the least of their worries. What about the Pullulus -- the rapid dark-matter expansion that caused the universe to literally tear itself apart at the seams, made people more violent, and, oh yeah, cause wizardy to stop working? That one got closer to ApocalypseWow towards the end.

* Myth/EgyptianMythology makes this trope OlderThanDirt: ''The Book of Going Forth By Day'' and the ''Coffin Texts'' (better known as the Egyptian Book of the Dead) describe how eventually the PrimordialChaos of Nun (the primeval waters) will consume all of the ordered cosmos, leaving only the gods Atum and Osiris in the eternal darkness (although one supposes that being gods, and Atum in particular being in [[ContinuitySnarl some versions]] of Egyptian myth being a creator god, they might create a ''new'' ordered universe, that's not really the point).

* If left unbeaten for long enough a time, this would be the result of how Lavos from ''VideoGame/ChronoTrigger'' does his work, growing stronger and stronger, by "stealing/copying" the "best" DNA from life forms on a planet, desolating them by method of Class 4, then sending his own "spawn" off to new planets to do exactly the same thing on another planet.

* The forfeit for losing the "game" in ''Manga/{{Bokurano}}'' is this: complete destruction of the loser's universe. Of course, the reward for the pilot of the winning team is instant death.
* ''LightNovel/ACertainMagicalIndex'': [[spoiler:One-Eyed Othinus can create and destroy universes with a thought]].

* What the Data Overmind, the Agency, and Mikuru's boss want to prevent indirectly by not allowing LightNovel/HaruhiSuzumiya to discover her powers and start consciously rewriting reality. In an unsettling twist, it's implied that [[spoiler:the Class X-4 has already happened at least once, about three years ago, and that's why Mikuru's organization was suddenly unable to time-travel past that point. No one else noticed anything amiss, since their memories were generated from scratch along with everything else in the new universe.]]

* In ''LightNovel/{{Slayers}}'', the destruction of the entire universe is the least you can expect if the [[DangerousForbiddenTechnique Giga Slave]] goes out of control... barring a DeusExMachina, anyway.

** Malekith the Accursed and the Dark Elves tried to use the Aether [[TheDarkTimes to plunge all the cosmos into an everlasting night]], bringing death and decay across the universe.

** Malekith the Accurse and the Dark Elves tried to use the Aether [[TheDarkTimes to plunge all the cosmos into an everlasting night]], bringing death and decay across the universe.

** Malekith the Accurse and the Dark Elves tried to use the Aether to plunge all the cosmos into an everlasting night, bringing death and decay across the universe.