History Main / MassTransformation

* ''Manga/JojosBizarreAdventureStoneOcean'': Most of the population of Orlando, Florida gets turned into snails when Heavy Weather is activated. However, since the effect is triggered by subliminal messages, it's debatable whether the transformations are a case of YourMindMakesItReal, or simply a mass hallucination. [[NoOntologicalInertia Everyone gets turned back]] after [[spoiler:Weather Report dies, deactivating the ability]].
* ''Anime/YuGiOhGX'': Yubel uses Professor Viper's bio bands to drain the students' energy and converts a large portion of the student body into her Duel Ghouls. By the end, the only people left are Jaden, the four transfer students, Alexis, Bastion, Hasslebery, and Blaire.
* The first episode of the 2018 reboot for ''Manga/GeGeGeNoKitaro'' has Kitaro and his friends investigate why an entire city turned to trees following [[DoesThisRemindYouofAnything an internet celebrity making a fool of himself in the middle of the crosswalk]]. [[spoiler:Charatomi broke the seal of the Yo-kai responsible not out of malicious intent, but rather purely for internet cloud.]]

* ''ComicBook/SonicTheHedgehogIDW'': The second story arc has Dr. Eggman create the Metal Virus with the intent of turning mass groups of people into Zombots. When the Zombots start raging out of control, Dr. Starline tries to get Eggman to do something about the problem but is merely dismissed as nitpicking. [[spoiler:Frustrated with his idol's seeming ineptitude, Dr. Starline calls upon the Deadly Six to help him, only for them to betray him and take control of the Zombots themselves in order to bring the world to ruin. Several issues later, Sonic and Silver use their Super forms to extract the Metal Virus from each Zombot and send it all to the Sun, undoing the zombification effects.]]

* The ''Franchise/JusticeLeagueOfAmerica'' crossover arc [=JLApe=] involves Gorilla City in a war against humanity after the murder of their king and transforming as many humans as possible into gorillas, including most of the League members.

* In the BackStory of ''WesternAnimation/BeautyAndTheBeast'''s live-action adaptation ''Film/BeautyAndTheBeast2017'', an enchantress visits the castle of a cruel and selfish prince and asks for shelter from a winter storm. When the prince refuses, the enchantress not only transforms him into a beast as punishment, she also transforms his servants into various objects such as a clock and candelabra, and it's stated that if the curse isn't broken in time, they'll be permanently transformed into lifeless bric-a-brac. Unlike the animated film, this version tries to justify the staff and guests falling under AesopCollateralDamage by pointing out that they could have spoken up on the enchantress's behalf, but [[BystanderSyndrome failed to do so]] and deserve to be punished, too. Mrs. Potts also remarks that the servants watched the young prince go from [[UsedToBeASweetKid a sweet little boy to a heartless tyrant]] at the hands of his father, but again never did anything to help, and thus bear some responsibility for his actions in the present.

* This trope is the basic premise of ''[[Literature/XanaduStoryVerse the Xanadu Story-verse]]''. Eric Winters [[UnwittingInstigatorOfDoom unwittingly fooling around with a magic raven mask]] results in everyone in a fan convention [[BecomingTheCostume being turned into what they were dressed up as]].

* Shows up multiple times in the ''VideoGame/DragonQuest'' series:

* ''VideoGame/WarioWorld'': Prior to the start of the game, Wario obtained a black jewel. The jewel turns out to be alive and destroys Wario's castle and transforms Wario's treasure into monsters.
* ''VideoGame/XenobladeChronicles'': Much of the sufficiently pureblooded [[spoiler:High Entia]] population are reverted into their original forms, telethia, shortly after the game's true villain takes center stage, robbing them of their bodies and minds and turning them into his servants.

[[folder:Visual Novels]]
* ''VisualNovel/SayaNoUta'': [[spoiler:Saya's ultimate purpose is to "bloom", releasing spores that transform all humans on Earth into [[EldritchAbomination whatever she is]].]]
[[/folder]]

* ''WesternAnimation/TheAvengersEarthsMightiestHeroes'': In the second episode of the [[Recap/TheAvengersEarthsMightiestHeroesS1E13GammaWorldPart2 Gamma World]] two-parter, The Leader projects a dome of gamma radiation over the entire city of Las Vegas, turning everyone inside into a gamma mutant.
* ''WesternAnimation/Ben10'': In "Be Afraid of the Dark," Zs’Skayr succeeds in firing a corrodium ray at the Earth, transforming every human on Earth into a horrifying mutant.
* ''WesternAnimation/Ben10UltimateAlien'': Vilgax damages the seal containing the Dagon, releasing an energy wave that morphs all of humanity into Esoterica soldiers of the Flame Keeper's Circle.

* ''WesternAnimation/JusticeLeague'' has Gorilla Grodd use his LegionOfDoom to gather items necessary to complete a device that he claims will amplify his MindControl to affect the entire world. When the device is activated, he reveals that it was never his goal - he simply hates humanity ''so much'' that the device will turn everyone into apes. His LegionOfDoom is not amused, and after the Justice League destroys the device, they even quip about it.

* ''WesternAnimation/RickAndMorty'': Twice in [[Recap/RickAndMortyS1E6RickPotionNumber9 Rick Potion #9]]. Rick's first iteration of a "love potion" was supposed to help Morty woo his schoolyard crush Jessica, only for it to mix with her flu and affect everyone. [[spoiler:The antidote to it makes it worse and morphs everyone into mantis-monsters that are homicidally in love with Morty]]. Rick makes an antidote for the antidote...which [[spoiler:transforms everyone on Earth into mutant Cronenberg monsters]].

* ''WesternAnimation/StarTrekLowerDecks'': In [[Recap/StarTrekLowerDecksS2E01StrangeEnergies "Strange Energies"]], Commander Jack Ransom is hit with the titular "Strange Energies" and gains godlike powers. He transforms the people of the planet the crew is helping into copies of himself and turns random objects into gym equipment. Doctor T'ana says "he's creating his own jacked utopia!"
* ''WesternAnimation/StevenUniverse'': During the Gem War, Pink Diamond is shattered by Rose Quartz in an effort to end the war and save Earth from her. [[spoiler:It is later revealed that they're actually the same Gem, and Pink had faked her own death to try and scare the Diamonds off of Earth.]] The other three Diamonds are so enraged at their sister's shattering that they combine their powers to send a corruption ray across the entire planet before leaving, transforming all the Gems on Earth into horrible monsters. Rose Quartz manages to use her shield to protect herself, Garnet, and Pearl from the blast.
* ''WesternAnimation/TeenageMutantNinjaTurtles2003'': This is Fast Forward's BigBad, Sh'okanabo's, plan. He uses his gene seeds to take control of the various species living on Earth and devour the planet's resources dry. The first time he does this, Raphael and Cody discover sunlight turns infected specimens back to normal. Sh'okanabo is furiously baffled as he has invaded countless planets with countless suns and never had this problem until now. Viral's analysis of the planet reveals sunlight combined with oxygen undoes the transformation. Sh'okanabo begins thinking of a way to eliminate the sun. The Fast Forward finale shows he converted the moon base's population.
* ''WesternAnimation/TeenageMutantNinjaTurtles2012'': The Kraang invade New York City for the season 2 finale and transform people into human-kraang hybrids with their new mutagen. The turtles, April, and Casey are forced to flee. When they return in season 3, they find the city deserted. The population has been taken to Dimension X for slave labor.

** Chapter 84 consists of a rerun of Chapter 28's BabyMorphEpisode courtesy of Kusuri's baby transformation drug. The first time it happened, there were seven girlfriends in the harem, and all the girls except Hakari were transformed. The second time it happened, there were 17 girlfriends in the harem, and all the girls who weren't transformed the first time became babies (11 girls in total.)

* ''Anime/AnimalDetectivesKiruminzoo '': Misa Hatori’s main goal. She started the animalian revolution to transform the entirety of the human population into animalians, a species of human animal hybrids who can animorph into both animals and human. Her plan was to no avail at the start however she was able to turn a good chunk of the Kamihama citizens into animalians thanks to a special gas created by Futatsugi, although this only affected those with animalian genes, which turns out is pretty common

* In ''Literature/SeasOfBlood'', one of your possible encounters is lifted directly from ''The Odyssey'', with you encountering a witch who transforms your crew into livestock. Depending on your choices, you may or may not suffer the same fate and turn into a pig (if you do, Game Over for you) - should you escape, you'll need to kill said witch to restore your crew.

* ''Website/GoAnimate'': Some videos have the troublemaker [[BabyMorphEpisode turning a crowd of people into babies]], animals, or even [[MesACrowd clones of themselves]].

* Duting the final confrontation in ''Literature/TheBookOfEve'', [[MotherEarth the Mother]] transforms the convent's defenders into a forest of hardy trees so that they can withstand Brother Abramo's assault.

* ''Literature/TheMagicSchoolBus'': In one of the books, Mrs. Frizzle turns herself and her students into bee/human hybrids as part of the lesson on bees.

*** On the Hylian side, it's revealed that the "curtain of twilight" that blankets Hyrule reduces humans, zoras, and gorons trapped under it to a invisible spirits, forever wandering and unable to interact with the world and unaware they have been changed and can't perceive Link but can still see and be harmed by monsters. The only exceptions are Zelda and Link, who are protected by the Triforce of Wisdom and Courage, respectively; Zelda retains her human form while Link undergoes a PainfulTransformation into a wolf. Monsters under the curtain of twilight instead turn into shadowy versions of themselves. Rats become squid-like shadow vermin, while other creatures are still mostly recognizable although gain some weird features. It is also hinted that the twilight monsters can turn the spirits into more monsters by attacking them, which is extra bad since the spirits can't harm the monsters.

*** On the Hylian side, it's revealed that the "curtain of twilight" that blankets Hyrule reduces everyone trapped under it to an invisible spirit, forever wandering and unable to interact with the world. The only exceptions are Zelda and Link, who are protected by the Triforce of Wisdom and Courage, respectively; Zelda retains her human form while Link undergoes a PainfulTransformation into a wolf.

* ''VideoGame/DragonQuestXI''
** One Tickington side quest sees the party visit the town of Moonahan from ''VideoGame/DragonQuestII''. In the original ''II'', the Princess of Moonbrooke was transformed into a dog by Hargon's forces and had to wait for the two Princes to find a mirror that could change her back. In the Tockington quest, however, the mysterious character altering the stories of the previous ''VideoGame/DragonQuest'' worlds made it where the Princess was able to change back prematurely at the expense of everyone ''else'' in Moonahan becoming dogs. She asks the Luminary to find the necessary item that will turn her into a dog again so the people of Moonahan can be uncursed.
** During Act 2 of the game, where Mordegon's monster army has taken over Erdrea, most residents of Octagonia have been transformed into monsters, including Jade. They're shown turning back to normal after Booga's defeat. Somewhat humorously, prior to defeating Jade and Booga's boss fights, you can talk to the monster [=NPCs=] and engage in the town's services.

* ''VideoGame/GoldenSun'': The residents of Kolima are all trees when Isaac and party arrive. They learn a tree deity spirit named Tret cursed the town after the town's lumberjacks cut down the Kolima Forest including him to build Lady McCoy=] a new palace.
[=* ''Franchise/TheLegendOfZelda'':

* ''Manga/AttackOnTitan'': Zeke Yeager, in a supreme dick move during the Marley arc, weaponizes his own spinal fluid to force this.
** Eldians are treated as second class citizens in the Marley empire. They're only allowed to hold limited social standing with direct approval of the government, and are repeatedly told to be ashamed of their ancestry. As such, many Eldians are conditioned into "repenting" by joining the military as voluntary Titan Bombs by consuming Zeke Yeager's spinal fluid. Using airships to drop over enemy forts, Zeke uses his scream to transform them after they drop out. The transformation in mid-air increases their mass, which lets them literally bomb into the structures, which they then mindlessly consume enemy soldiers.
** Zeke does this to Levi's squad in order to buy time for his escape and get rid of Levi. The soldiers in question had consumed wine that Zeke had laced with said spinal fluid, resulting in Levi having to kill them when they are all transformed and try to eat him alive. Needless to say, when Levi catches up with Zeke, he is ''pissed.''

* ''Manga/The100GirlfriendsWhoReallyReallyReallyReallyReallyLoveYou'': Chapter 84 consists of a rerun of Chapter 28's BabyMorphEpisode courtesy of Kusuri's baby transformation drug. The first time it happened, there were seven girlfriends in the harem, and all the girls except Hakari were transformed. The second time it happened, there were 17 girlfriends in the harem, and all the girls who weren't transformed the first time became babies (11 girls in total.)

* ''VideoGame/GoldenSun'': The residents of Kolima are all trees when Isaac and party arrive. They learn a tree deity spirit named Tret cursed the town after the town's lumberjacks cut down the Kolima Forest including him to build Lady McCoy a new palace.
* ''Franchise/TheLegendOfZelda'':

* ''WesternAnimation/StarTrekLowerDecks'': In [[Recap/StarTrekLowerDecksS2E01StrangeEnergies "Strange Energies"]], Commander Jack Ransom is hit with the titular "Strange Energies" and gains godlike powers. He transforms the people of the plant the crew is helping into copies of himself and turns random objects into gym equipment. Doctor T'ana says "he's creating his own jacked utopia!"