History AdaptationSpeciesChange / FanWorks

** Rei Ayanami from ''Anime/NeonGenesisEvangelion'' goes from a human Clone to a [[HalfHumanHybrid half-human, half-Gigan]] since her father is [[Manga/JoJosBizarreAdventure Wamuu the Pillar Man]].

* ''Fanfic/TheTwilightMan'': A major reveal is that [[spoiler:Mary Joestar]] is [[HalfHumanHybrid half-human, half Nightman (Pillar Man)]] rather than pure human like in ''Manga/PhantomBlood''. [[spoiler:This makes her son Jonathan Joestar and his descendents [[UnevenHybrid uneven hybrids]] with Nightman heritage rather than pure humans]].

[[AC:''Franchise/{{RWBY}}'']]
* ''Fanfic/TheUnseenHunt'': Ozpin is a complete [[BadassNormal muggle]] instead of an immortal, body-jumping wizard from a previous version of humanity, Velvet is a human instead of a Faunus, [[spoiler:and Blake, Adam, Ruby and Cinder are all intelligent Creatures of Grimm instead of Faunus, a human Silver-Eyed Warrior, and a human Maiden respectively]].

* ''Fanfic/ValesUnderground'' takes place in a real-world setting. So various [[LittleBitBeastly Faunus]] characters in canon who appear in the story can be assumed to be just plain humans.

* ''Fanfic/UltimateSpiderWoman'' does this to ''Franchise/SpiderMan'' villain the Chameleon, who is turned from a human (who, depending on how he's written, is either a MasterOfDisguise or a mutated human with ShapeShifting powers) into a mutant, [[RelatedInTheAdaptation and the brother of]] ''Franchise/XMen'' villain Mystique.

* [[Anime/PuellaMagiMadokaMagica Madoka]] in ''[[https://archiveofourown.org/works/30333318/chapters/74772423 Moebius]]'' is revealed to have Quincy ancestry from the Manga/{{Bleach}} half of the crossover, making her, her brother, and one of her parents not quite regular humans as they were in Madoka's home series.

* [[Anime/PuellaMagiMadokaMagica Madoka]] in ''[[https://archiveofourown.org/works/30333318/chapters/74772423 Mobius]]'' is revealed to have Quincy ancestry from the Manga/{{Bleach}} half of the crossover, making her, her brother, and one of her parents not quite regular humans as they were in Madoka's home series.

* {{Justified}} in ''Fanfic/{{Medicated|Trope}}''. Anne, Sasha and Marcy are originally humans, like in the show, but they have spent their entire lives as a frog, a toad and a newt.

* {{Justified}} in ''Fanfic/{{Medicated}}''. Anne, Sasha and Marcy are originally humans, like in the show, but they have spent their entire lives as a frog, a toad and a newt.

* Played with in ''Fanfic/{{Medicated}}''. Anne, Sasha and Marcy are originally humans, like in the show, but they have spent their entire lives as a frog, a toad and a newt.

[[AC:''WebAnimation/{{RWBY}}'']]
* In the ''WebAnimation/{{RWBY}}''/''Franchise/MarvelCinematicUniverse'' FusionFic ''[[https://www.fanfiction.net/s/11722542/1/In-Shades-of-Red-and-Gold In Shades of Red and Gold]]'', several characters from ''WebAnimation/{{RWBY}}'' are changed from humans or faunus to being [[ComicBook/XMen mutants]] (even though mutants don't exist in the ''Franchise/MarvelCinematicUniverse''), including Ozpin, Velvet, and Blake, and implied with Goodwitch and Coco (possibly also Weiss and team JNPR). As well, Beacon Academy becomes Beacon Institute, the West Coast equivalent of the Xavier Institute, even being cofounded by Ozpin and Xavier. WordOfGod states that Ruby and Yang aren't mutants. Also, Zwei is a RobotDog.
* Used so much in the ''WebAnimation/{{RWBY}}''/''World of Ere'' story ''[[https://archiveofourown.org/works/9448874/chapters/21376838 Not Your Saint George]]'' that it would be easier to list the ''[=RWBY=]'' characters who have appeared so far that ''haven't'' had their species changed [[note]]Jaune, Jaune's family, Cardin[[/note]]
** Pyrrha is Pyrrhanykos, a young[[note]]Well, young for a dragon. She notes that, for dragons, saying you've been somewhere for thirty years is equivalent to saying you've been there for twenty minutes[[/note]] red dragon.
** [[spoiler: Ruby, Yang, and their family are werewolves, with Summer, Raven, and Qrow also being [[OurOrcsAreDifferent orcs]]]].
** [[spoiler: Nora is a goblin, while Ren is a hob (a catchall term for people who are part-orcs)]]
** [[spoiler: Winter and Weiss are [[WingedHumanoid hailene]]]].
** [[spoiler: Blake is a cat hengeyokai]].

* ''Fanfic/DateAReLive'': In the [[LightNovel/DateALive source material]], [[spoiler:Tohka Yatogami was born a [[PureMagicBeing Pure Spirit]] as revealed in Volume 18, in this fanfic, she was born a human prior to becoming one of the Sephira Spirits]].

* ''Literature/{{Animorphs}}'':
** ''Fanfic/AllAssortedAnimorphsAUs'': Ax is a werewolf in "What if they all went to [[Franchise/HarryPotter Hogwarts]]?" and a human in "What if they were imprisoned?" and "What if they were pirates?" instead of an [[OurCentaursAreDifferent Andalite]]. All the aliens are humans in "What if they were in the Hunger Games?" and "What if they were in Emelan?" as well.
** In ''Fanfic/{{Daemorphing}}'', Euclid is Nora's [[BondCreatures daemon]] instead of a regular dog. [[spoiler:Also, Tom becomes a Hork-Bajir [[ShapeshifterModeLock nothlit]], a morph he never even acquired in canon.]]
** In ''Fanfic/APrincessATreehuggerAndASpaceCadetWalkIntoALibrary'', Ax is a human instead of an Andalite.
* ''WesternAnimation/{{Gargoyles}}'';
** "[[https://www.fanfiction.net/s/9672481/1/Guardian-of-the-People Guardian of the People]]", Elisa is a gargoyle from the beginning; the first chapter explores how she was taken in by her 'grandfather' as an egg after most of her gargoyle clan were killed or died of old age, and was essentially raised by the Mazas as a sibling to Derek and Beth after Peter moved to New York due to her slow growth rate.
** “[[https://www.fanfiction.net/s/13599530/1/An-Alternate-Life An Alternate Life]]” depicts a world where the Manhattan Clan and Demona are all human and Elisa is the last gargoyle survivor of Wyvern.
* ''WesternAnimation/MyLittlePonyFriendshipIsMagic'':
** In ''Fanfic/{{Delusions}}'', Celestia and Luna were born as mules before they ascended to alicornhood. In canon, there's nothing to suggest that they weren't always full-blooded ponies.
** ''Fanfic/ADiplomaticVisit'': [[spoiler:In canon, Queen Novo was a hippogriff who changed into a seapony. In this universe, she was always a seapony. The same holds true for her daughter Princess Skystar, her sister Ocean Flow, and her niece and nephew Silverstream and Terramar. Subverted with the siblings' father Sky Beak, whom Spike initially assumes was also a seapony originally, before he corrects him and explains he was born a hippogriff and changed into a seapony with the Pearl of Transformation.]]
** ''[[https://www.fanfiction.net/s/7921003/1/The-HFiles The H-Files]]'' is a {{Crossover}} with ''Series/TheXFiles'' where Mulder and Scully are ponies.
** The premise of ''Fanfic/HeartOfTheForest'' is that almost every major character is a different species. Applejack is a deer, Fluttershy is a draconequus, Pinkie Pie and Rainbow Dash are griffons, Rarity is a river serpent, and Twilight is a dragon (all instead of ponies); Spike is a pony (instead of a dragon); and Discord is a hinny (instead of a draconequus).
** ''[[https://www.fimfiction.net/story/494299/the-long-game The Long Game]]'': Hydia, who was originally a human(ish) witch in ''WesternAnimation/MyLittlePonyTheMovie1986'' and ''WesternAnimation/MyLittlePonyAndFriends'', is recast as a lamia.
** In the ''WesternAnimation/MyLittlePonyEquestriaGirls'' films, Spike is a dog in the human world and is the human Twilight's loyal pet. In ''Fanfic/YugiohEQG'' Spike is human like the rest of the characters and is Twilight's adopted little brother.
* ''WebAnimation/{{RWBY}}''
** In the ''WebAnimation/{{RWBY}}''/''Franchise/MarvelCinematicUniverse'' FusionFic ''[[https://www.fanfiction.net/s/11722542/1/In-Shades-of-Red-and-Gold In Shades of Red and Gold]]'', several characters from ''WebAnimation/{{RWBY}}'' are changed from humans or faunus to being [[ComicBook/XMen mutants]] (even though mutants don't exist in the ''Franchise/MarvelCinematicUniverse''), including Ozpin, Velvet, and Blake, and implied with Goodwitch and Coco (possibly also Weiss and team JNPR). As well, Beacon Academy becomes Beacon Institute, the West Coast equivalent of the Xavier Institute, even being cofounded by Ozpin and Xavier. WordOfGod states that Ruby and Yang aren't mutants. Also, Zwei is a RobotDog.
** A bunch in the ''WebAnimation/{{RWBY}}''/''Literature/TheHobbit'' FusionFic ''[[https://www.fanfiction.net/s/11852303/1/Rise-of-a-Star-Knight Rise of a Star Knight]]'' and its sequel (and the ''Literature/TheLordOfTheRings'' to its ''Literature/TheHobbit'') ''[[https://www.fanfiction.net/s/12404778/1/Knights-of-Remnant-The-Ring-of-Darkness Knights of Remnant: The Ring of Shadows]]'':
*** First, goblins are actually faunus, or rather, [[WasOnceAMan were faunus]], who hide in the mountains and stayed separated from the rest of their species for so long they evolved into something else.
*** Thorin and his party are replaced by Jaune and his party of humans and faunus, with the dwarven civilization as a whole replaced by [[TheClan the Valkyrie clan]] (as in, Nora Valkyrie's massive extended family, who are master miners, stoneworkers, and resident [[DugTooDeep people who delve to greedily and too deep]])
*** Elves are replaced by humans and faunus, depending on the group.
*** Uruk-hai, trolls, [[spoiler:Smaug]], and other such things are Grimm, though [[spoiler: Smaug WasOnceAMan, the Mad King of Vale [[TheCorrupter Felix]](yes, ''that'' [[WebAnimation/RedVsBlue Felix]])]].
** Used so much in the ''WebAnimation/{{RWBY}}''/''World of Ere'' story ''[[https://archiveofourown.org/works/9448874/chapters/21376838 Not Your Saint George]]'' that it would be easier to list the ''[=RWBY=]'' characters who have appeared so far that ''haven't'' had their species changed [[note]]Jaune, Jaune's family, Cardin[[/note]]
*** Pyrrha is Pyrrhanykos, a young[[note]]Well, young for a dragon. She notes that, for dragons, saying you've been somewhere for thirty years is equivalent to saying you've been there for twenty minutes[[/note]] red dragon.
*** [[spoiler: Ruby, Yang, and their family are werewolves, with Summer, Raven, and Qrow also being [[OurOrcsAreDifferent orcs]]]].
*** [[spoiler: Nora is a goblin, while Ren is a hob (a catchall term for people who are part-orcs)]]
*** [[spoiler: Winter and Weiss are [[WingedHumanoid hailene]]]].
*** [[spoiler: Blake is a cat hengeyokai]].
** ''Fanfic/ValesUnderground'' takes place in a real-world setting. So various [[LittleBitBeastly Faunus]] characters in canon who appear in the story can be assumed to be just plain humans.

* In "[[https://www.fanfiction.net/s/10304728/1/Boston-Bound-Fae Boston Bound Fae]]", a crossover with ''Series/LostGirl'' and ''Series/RizzoliAndIsles'', characters like Jane Rizzoli, Barry Frost and Charles Hoyt are all 'reinvented' as Fae; Jane is a wolf-shifter, Frost is a siren, and Hoyt is a Torak (a Fae who feeds on fear the blood of their victims).

* The ''Anime/PokemonTheSeries''/''WesternAnimation/BeastWars'' crossover ''[[https://www.fanfiction.net/s/3444797/1/Pokemon-Wars-Transformers-The-Beginning Pokémon Wars: Transformers]]'' has the Maximals and Predacons land on the Pokémon World rather than Prehistoric Earth and thus use Pokémon as their disguise forms instead (which also results in most of them [[AdaptationNameChange using new aliases]]);
** Optimus Primal is a Blastoise.
** Megatron is a Feraligatr.
** Cheetor becomes a Houndoom and is renamed Blaze-Hound.
** Rhinox becomes an Aggron and is renamed Aggronix.
** Rattrap becomes a Raichu and is renamed Shockrat.
** Dinobot becomes a Charizard and is renamed Chari-Tron.
** Waspinator becomes a Beedrill and is renamed Bee-Driller.
** Terrorsaur becomes an Aerodactyl and is renamed Aerosaur.
** Tarantulus becomes an Ariados and is renamed Ariadox.
** Scorponock becomes a Scizor and is renamed Scizornex.

* In the ''Series/BuffyTheVampireSlayer''/''Series/{{Supernatural}}'' crossover "[[https://www.fanfiction.net/s/12096229/1/Paschendale Paschendale]]", more standard monsters like vampires and werewolves are basically a subtle mix of the mythology of both shows, such as vampires being vulnerable to stakes and Oz still able to lock himself away when he transforms. However, Whistler and Anya are changed from being demons to angels; Whistler is an angelic watcher known originally as Sariel, and Anya is Naamah, an angel of physical love who has become warped after seeing love turn to physical violence on so many occasions (Castiel undoes her wish by removing her grace).
* In as much as machines can have a species, in the ''Franchise/{{Transformers}}''/''Franchise/StarWars'' crossover "[[https://www.fanfiction.net/s/12387504/1/Sparks-Among-the-Stars Sparks Among the Stars]]", exposure to the Allspark changes R2-D2, the Millennium Falcon and [[spoiler:the Death Star]] into Transformers, granting the vehicles full sentience.

* In ''[[https://www.fanfiction.net/s/10107262/1/A-Grimm-Possibility A Grimm Possibility]]'' (a ''WesternAnimation/KimPossible''/''Series/{{Grimm}}'' crossover) and its sequels, not only are Kim and Anne now Grimms (with the possibility that Jim and Tim will also manifest later), but many of Kim’s friends and enemies are different kinds of Wesen, including;
** Bonnie Rockwaller is a Ziegavolk who flees school after Kim identifies her.
** Ron is an eagle-esque Wesen (identified as a Mannschaft Falken, a species that didn't appear in the original show), who becomes Kim's boyfriend.
** Tara is an Eisbiber whose parents run a hardware store.
** Monique is a Luisant-Pêcheur who is rescued from her abusive adopted Skalengeck parents by Kim and Anne.
** Shego is a Dämonfeuer pursuing her own vendetta.
** Adrenna Lynn is a Ende der Zieten Grimm who tries to capture and brainwash Kim to join her.

* MassiveMultiplayerCrossover ''Fanfic/WithPearlAndRubyGlowing'' takes place in a modern setting, so several non-humans become humans, fantastical pets become real animals (such as [[WesternAnimation/LiloAndStitch Stitch]], an alien that pretends to be a dog, becoming an actual dog), and some animals that aren't convenient for a city are changed to smaller animals ([[WesternAnimation/GravityFalls Waddles]] the pig becoming a guinea pig). Averted in cases of RuleOfFunny: [[Franchise/{{Frozen}} Sven]] is still a reindeer, and ends up trapped in Kristoff's apartment after some AlcoholInducedIdiocy.

* ''Fanfic/InkyFuture'' is a crossover between VideoGame/MegaManX and {{Franchise/Splatoon}} taking place in the setting of the latter in a timeline where X is discovered 12,000 years behind schedule long after humanity has gone extinct. As a result, almost every {{Franchise/MegaMan}} character from after the [[VideoGame/MegaManClassic Classic time period]] (aside from X and Zero or characters from alternative time periods) is either an Inkling, an Octoling or some other non-robotic species, as reploids were never created by Dr. Cain and robotics is largely a niche field of study in the ''Splatoon'' setting. Professor Gaudile in particular becomes an ''actual platypus''.

*** Thorin and his party are replaced by Jaune and his party of humans and faunus, with the dwarven civilization as a whole replaced by [[TheClan the Valkyrie clan]](as in, Nora Valkyrie's massive extended family, who are master miners, stoneworkers, and resident [[DugTooDeep people who delve to greedily and too deep]])

*** Uruk-hai, trolls, [[spoiler:Smaug]], and other such things are Grimm, though [[spoiler: Smaug WasOnceAMan, the Mad King of Vale [[TheCorrupter Felix]](yes, ''that'' [[WebAnimation/RedVsBlue Felix]])]].

* ''Fanfic/InkyFuture'' is a crossover between VideoGame/MegaManX and {{Franchise/Splatoon}} taking place in the setting of the latter in a timeline where X is discovered 12,000 years behind schedule long after humanity has gone extinct. As a result, almost every {{Franchise/MegaMan}} character from after the [[VideoGame/MegaManClassic Classic time period]] (aside from X and Zero or characters from alternative time periods) is either an Inkling, an Octoling or some other non-robotic species. Professor Gaudile in particular becomes an ''actual platypus''.

* ''Webcomic/DisneyHighSchool:'' All of the main characters are humans, even if they were [[WesternAnimation/TheLittleMermaid1989 mermaids]], [[WesternAnimation/{{Hercules}} gods]], [[WesternAnimation/WreckItRalph video game human characters]] or [[Film/WhoFramedRogerRabbit Toons (human ones or of other species)]] in their respective movies. The creator has noted that she won't be trying to humanize outright animal characters, however; perhaps the most radical change so far is [[WesternAnimation/Frozen2013 Kristoff]]'s family, [[{{Gonk}} who still look pretty trollish]].

* MassiveMultiplayerCrossover ''Fanfic/WithPearlAndRubyGlowing'' takes place in a modern setting, so several non-humans become humans, fantastical pets become real animals (such as [[WesternAnimation/LiloAndStitch Stitch]], an alien that pretends to be a dog, becoming an actual dog), and some animals that aren't convenient for a city are changed to smaller animals ([[WesternAnimation/GravityFalls Waddles]] the pig becoming a guinea pig). Averted in cases of RuleOfFunny: [[WesternAnimation/Frozen2013 Sven]] is still a reindeer, and ends up trapped in Kristoff's apartment after some AlcoholInducedIdiocy.

** [[spoiler: Ruby, Yang, and their family are werewolves, with Summer, Raven, and Qrow also being [[OurOrcsAreDifferent orcs]]]].