Fusion Fic - TV Tropes

A Fusion Fic is a variety of crossover fic where two or more works are merged together into one (hopefully) cohesive setting. The most common types are:

• Transplanted Character Fic: The main characters of work A are placed in the setting of work B; they may re-enact work B's plot with some changes, or go about an entirely new plot.
• Film Fic: The characters of work A are actors playing out the plot of work B.
• Setting Merge: Two different settings are brought together in some way. This can be something as simple a secret connection popping up, all the way up to creating a completely new setting using elements of the two.
• Complete Merge: As above, but the two casts are also melded into Composite Characters.

Sometimes overlaps with Meta Fic and Elsewhere Fic. Compare the more typical Intercontinuity Crossover. Not to be confused with Patchwork Fic, where a fic merges elements from multiple adaptations of a single parent work.

See also Role Swap AU, where the characters within a single work switch roles with each other.

---

Examples:

• A rare commercial variant of this would be the "Amalgam Universe" jointly created by Marvel and DC, in which their two universes and their inhabitants were merged in a literal fusion, where "Character X + Character Y = Character Z, who partakes of both". For example, Doctor Doom and Doomsday combine to form "Doctor Doomsday", Batman and Wolverine turn into "Dark Claw", Captain America and Superman become "Super-Soldier", etc.
• Anime X Marvel: The series blends both elements of anime and comic books into one setting.
  • My Hero Academia: Armored Adventures has Izuku Midoriya being Ironman and U.A. High's Class 1-A having students in the form Shang-Chi, T'Challa and Pavitr Prabhakar.
  • Danmachi: The Last King has gods from the Marvel Universe living alongside those from Is It Wrong to Try to Pick Up Girls in a Dungeon?.
  • Spy x Family Project: W.E.B. combines Spider-Man Noir and Spy X Family. Loid Forger is an agent of WISE and also Spider-Man while Yor was originally part of the Black Widow program alongside Natasha Romanoff before fleeing and taking up the life of an assassin.
  • Chainsaw Man Son Of Deadpool shares elements of the Chainsaw Man manga and the comics, particularly the Cancerverse storyline. The Devils are the unfortunate results of the superheroes defeating Death.
  • Phase 3 introduces The Defenders series where various elements of anime and Marvel Comics are mixed together to form a Shared Universe. Groups like Soul Reapers and Jujutsu Sorcerers are well aware of one another.
• The Avengers fic The Snow Queen is the Hans Christian Andersen story The Snow Queen told with Captain America as Gerda, Iron Man as Kay, and various Avengers, Avengers villains, and other superheroes as all the supporting characters, several of whom don't appear in the original story, but fit perfectly into the original story's various settings. It's written in a very authentic, fairy-tale-ish style similar to Andersen's, and Avengers fans will take great delight in recognizing which Marvel characters the usually vaguely described and nameless or ambiguously-named supporting characters are supposed to be.
• Battle Spirit features Joseph Joestar as the Avatar training to defeat a trio of dark spirits.
• Ben 10: Unlimited starts as a simple crossover between Ben 10 and Justice League, but continues through Unlimited Justice as the latter part is eventually fused with Young Justice and also has the occasional Canon Immigrant from Teen Titans. A pseudo-sequel, My Alien Academia, brings in My Hero Academia as well.
• BlazBlue Alternative: Remnant is a fusion of RWBY and BlazBlue, the premise being that it's a retelling of the former where two settings are merged together. Characters such as Ragna, Jin, Noel, Tsubaki, and Makoto are part of the world of Remnant and attend combat school alongside the RWBY characters, Terumi and Relius work alongside Salem, Penny is a Murakumo Unit rather than an android, the Creatures of Grimm are revealed to be comprised of Seithr, and one of Ozpin's past incarnations was Bloodedge.
• The main premise of Blood on the Hands of a Healer is what happens if the storyline of Re:CREATORS took place in the setting of Kamen Rider Ex-Aid.
• Blood Ties (Naruto/Skyrim) is a crossover between Naruto and The Elder Scrolls whose premise is that the land of Elemental Nations is one and the same with the Elder Scrolls' Akavir.
• Breath Waker is a fusion of Homestuck and The Legend of Zelda: The Wind Waker. John taks the place of Link, on a quest to rescue his sister Jade after she was kidnapped by a flying monster and to awaken and master the powers of Breath; Rose and the crew of the Grimdark take the role of Tetra and her pirates, although the love interest role is played by Roxy; the trolls of Dragonroost Island, who are given their butterfly wings at maturity by the dragon Pyralspite, play the role of the Rito.
• Children of an Elder God is Neon Genesis Evangelion with the pseudo-Christian stuff replaced with H. P. Lovecraft, right down to Misato wearing an elder sign instead of a cross.
• Child of the Storm blends the backstories of Harry Potter, Marvel Cinematic Universe, Marvel Comics^note , Smallville, DC Comics, The Sandman (1989), The Dresden Files and sprinkles in hints of Good Omens to boot.
• Christian Potter Chandler replaces Harry Potter with Chris-chan, to see how his antics and ridiculous personality affect the story.
• While originally planned as something more along the lines of a Plot Twist at first, two of the fics in MF217's Citadel of the Heart continuity were planned from the start to be a Shared Universe rather than take place in a separate universe but a still shared continuity regardless. As a direct result of this, Sword Art Online: Special Edition and Reflection Code are fanfics based off of Sword Art Online and Code Lyoko respectively, but rather than simply tell the story within the same fic, two separate characters are used as a framing device so that the two different franchises remain independent of each other when it comes to the otherwise shared cast and setting. As a result, elements from both series are used to explain certain technological advancements as well as some of the backstory in both universes as well as how some of the A.I.s have the abilities they do. Every once in a while the canon cast members from both series will occasionally get a chance to meet each other, but these moments are few and far between considering one fic takes place in Japan and the other in France.
• Code Geass: Paladins of Voltron: Between Code Geass and Voltron: Legendary Defender, in this story, the members of the Ashford Student Council (except for Nina) become the Paladins of Voltron.
• Code Prime: Between Aligned continuity of Transformers and Code Geass. Among other things, it's confirmed that Sakuradite and Energon are synonymous and the Decepticons are the ones behind the Britannian Empire. The final chapter of R1 reveals that Geass may possibly have originated from Unicron.
• Crystalforged, a branch timeline of The Eventide Verse, blends together My Little Pony: Friendship Is Magic with Ironsworn: Starforged by replacing the human inhabitants of the Forge with ponies and other creatures who fled their home planet in the wake of their own version of the Sun Plague.
• Dæmorphing is about how the events of Animorphs would be different if the setting had the cosmology of His Dark Materials, but no characters from the latter appear.
• The crossover fan fic A Dark Knight Over Sin City explores the concept of Batman and his rogues in Sin City.
• Decks Fall Everyone Dies has the characters of Yu-Gi-Oh! The Abridged Series in the general plot from Moulin Rouge!
• A Different Kind of Truth has Johnny Joestar from Part 7 of JoJo's Bizarre Adventure replace Yu Narukami of Persona 4, disability and bitterness included. It also makes Personas closer to Stands.
• Digimon Fusion Kai intertwines the Digimon and Dragon Ball Z into a long-running fusion series. It has been previously and been simply called Digimon Fusion (not to be confused with the English language version of Xros Wars) or D-Fusion in the past. As of 2010, it has been revived and rebranded with the Kai label.
• Dinner For One Mouse is an otherwise unaltered Dinner for One featuring the main original characters from the Chip 'n Dale: Rescue Rangers fanfic Closer Than a Brother playing that old Vaudeville sketch. The actress Sophia Marskov stars as Miss Sophie, and her butler Jules Crissen plays James. It was even written, greenlit by the author of Closer Than a Brother, and published on New Year's Eve 2006.
• Dragon Ball: Superman: A fanfic in which Clark Kent was born with a tail, finds the Dragon Balls with Bulma Briefs, and trains under Son Gohan. And this is just the beginning.
• Obscure doujinshi series Mythic Quest has a whole non-canonical edition crossing over with .hack, which involves Anaya as Emma Weilant and John as Harald Hoerwick, along with other omakes of Balmung as their son and .hacks Aura as their daughter.
• "It's Five By Five" is a crossover of Dragon Age II with Angel. It features Anders/Vengeance as Angel/Angelus, Sebastian as Holtz, Female Hawke as Buffy, Alistair as the Mayor of Sunnydale, and Carver as a vampire, among others.
• The Endless Pantheon fanfic series combines The Dresden Files and Stargate SG-1. The Goa'uld are a race of godlings who fell from grace millennia ago after a disastrous war with the faerie Courts, alien technology is actually highly-advanced Magitek, and Goa'uld once prized wizards, or hok'taur, as the perfect host. After a trip into the Nevernever dumps him on a Goa'uld world, Harry Dresden ends up accidentally usurping a System Lord's mantle and starts contributing to the galactic chaos SG-1 kicked off.
• Equestria Girls: Friendship Souls has Bleach happening within the world of My Little Pony: Equestria Girls, with the canon Bleach characters replaced by MLP characters.
• Falling Stars dumps Lucky Star characters into the Fallout universe circa Fallout 3.
• Fallout: Equestria presents a possible future of My Little Pony: Friendship Is Magic using the general plot, tone and setting elements of Fallout 3, with a bit 1984. The Vaults become Stables, nuclear weapons are replaced with "megaspells" and so on.
• Fallout: SG-1 is a blending of Fallout and Stargate; In this universe, SG-1 is composed of an old Daniel Jackson who lived most of his life on Abydos, Veronica Santangelo, Arcade Gannon, and of course Teal'c. Carter was an astronaut for the USSA, which fits what regularly occurs to her during the show's regular visits to alternate realities.
• The Boat Scene A Familiar's Confession is a Hey Arnold! and The Familiar of Zero crossover with a twist - instead of Louise summoning a Hey Arnold character to be her familiar, as is the usual route of Familiar of Zero crossover fics, Louise is replaced by Helga, and Saito is replaced by Arnold.
• A somewhat popular Fandom-Specific Plot for Fate/stay night is an example of Multiple-Choice Past where "Shirou was [another series' character] before he lost his memories in the Fuyuki fire and was presumed dead by his family". Fate/Reach Out, for example, has a pre-Holy Grail War Shirou replace Yu Narukami.
• The Fifty Shades Series is a retelling of the Fifty Shades of Grey series using characters and concepts from Red Dwarf.
• The First Saniwa, a Touken Ranbu/Onmyoji crossover that merges aspects of both games' canons and uses one game's canon to explain the other's. For example, Yorimitsu is the ancestor of the present day saniwa, the canonical fact that Onigiri isn't actually the personification of the sword he represents allows him and Higekiri to exist in the same universe, and Kuro Seimei is actually the work of Historical Revisionists.
• A Goddess Comes to Call is a fusion between Bubblegum Crisis and Ah! My Goddess, where Linna is the one who accidentally summons Belldandy and wishes that she would stay by her side forever - Keichii instead wishes for the girl who would be perfect for him, and ends up with Chihiro Fujimi.
• The Halloween Hack replaces Ness with the protagonist of Brandish, Varik. In-universe, some people even think Varik is Ness.
• Her Scarlet Letter mixes Harvest Moon: Animal Parade with The Scarlet Letter. Angela has an affair with a married man and ends up pregnant, but refuses to name her child's father.
• HoloFunk is a Friday Night Funkin' overhaul mod featuring the cast of hololive in an Alternate Universe with the tone of FNF. It also features multiple characters from several other sources ^note  and the original Friday Night Funkin' cast rewritten into the context of the HoloFunk universe, with most being featured in the backstory.
• Inside Falls is a fanfic that combines characters from many works into the story of Gravity Falls, but most of the main cast is composed by characters from Undertale and Steven Universe. Giving a example with the fifth main characters, Chara replaces Dipper, Frisk replaces Mabel, Pearl replaces Stan, Asriel replaces Soos and Lapis replaces Wendy.
• Some characters from other works replace a few of the characters in the original JoJo's Bizarre Adventure Canon in Vaguely Recalling JoJo:
  • Magician's Red is replaced by Blaziken and GEB happens to be its weakness because GEB is a Water-type.
  • Negi Springfield replaced Ebony Devil.
  • Hoshi is the mugger who gets to be on the receiving end of Rubber Soul's coconut backbreaker.
  • Bridget replaces Nena and Roger the Teddy Bear is his Stand, Empress.
  • Captain Falcon replaces ZZ and compliments Kakyoin for doing a Boost Fire with a modern car.
  • Blossom replaces High Priestess and she effortlessly beats up Jotaro's group, at first.
  • Bast is replaced with Taokaka.
  • Khnum is now Oingo's belt buckle, and to use its powers, Oingo yells a transformation phase.
  • Makoto Shishio replaces Chaka.
• Just an Unorthodox Thief combines Fate/Zero and Lupin III. Lupin the Third in this fic was a well-known thief in the Nasuverse and all his exploits are well known and documented. He also stole several historical artifacts for Mages hoping to get into the Holy Grail War, including Hassan's mask. Thus leading to him being summoned as the Servant Assassin by Kirei.
• Lantern Prime has Optimus Prime as the indirect source of the Manhunter robots and the first Green Lantern.
• Last Child of Krypton: Between Neon Genesis Evangelion and DC Comics. Shinji is Superman, Kaji is the second Batman, having been trained by Bruce Wayne, Kyoko was an Amazonian, Asuka takes on the mantle of Wonder Woman, Toji becomes a Green Lantern, Kaworu is essentially Black Adam, Rei is essentially Supergirl, and Naoko Akagi is essentially Galatea. There is mention made of Barry Allen, Shinji meets the Martian Manhunter before the latter expires, Diana gives Asuka and the others refuge after the Zeruel incident, Atlantis was destroyed by Second Impact, and several classic DC villains make an appearance in the story.
• The Last of Us Series are a retelling of The Last of Us games but using Once Upon a Time (2011) characters.
• Legacy of the Red Sun has Kal-El land on Tatooine after Luke is killed.
• The Legend of Eevee: Pokéflute of Time is exactly what it sounds like: Ocarina of Time with Pokémon.
• Lelouch of the Wings of Rebellion takes away the supernatural elements of Code Geass from its plot and replaces them with those of Persona 5, with prince-in-hiding Lelouch becoming the Trickster instead of a Geass User, and leaving everything else pretty much the same. The Code Geass cast is also mostly the same in characterization and personality, but their circumstances are just different enough to keep things interesting.
• Magical Pony Lyrical Twilight is a fanfic that asked the question "What if the Jewel Seeds of Magical Girl Lyrical Nanoha landed My Little Pony: Friendship Is Magic's Equestria?" In this case, the entire Jewel Seed crisis would end differently and less traumatically. Later works by the same author would put the citizens of Ponyville through the events of Magical Girl Lyrical Nanoha A's and Magical Girl Lyrical Nanoha Striker S.
• A Man of Iron is a crossover that puts various characters from the Marvel Comics into the world of A Song of Ice and Fire/Game of Thrones and adapts them to the Medieval European Fantasy setting; in particular, Tony Stark is Ned Stark's cousin, and he's the mysterious knight known as "Iron Man".
• The Fanfic Martian Manhunter is an interesting case. No characters are replaced; rather, Veronica Mars, along with her backstory and supporting cast, are shoehorned into the background of Buffy the Vampire Slayer's Sunnydale... The twist is she still has all her Neptune memories, including who killed Lily, and the entire series of Buffy the Vampire Slayer, which to her was, until a certain point, entirely fictional.
• Mercedes Lackey wrote the short story "Moving Targets", which is a fusion of Heralds of Valdemar Valdemar and Scooby-Doo. It has four Herald trainees and a kyree in a green flower-painted wagon solving a "Scooby-Doo" Hoax. It even includes the line "And I would have gotten away with it, too, if it hadn't been for you meddling Heralds".
• Tears of Revelry is the story of Mobile Suit Gundam Wing told in the world of Avatar: The Last Airbender as a sequel of sorts instead of The Legend of Korra. The main events start 195 years after A:TLA concludes, and while the plot changes course eventually, the overall story remains. Supplemental material can be found in Tales From Gundam Island.
• My Hero School Adventure Is All Wrong As Expected is a story that integrates the Ore Gairu cast as native inhabitants of the My Hero Academia world. To wit, Hachiman, Yukino, Yui, Hayato, Yumiko, and Tobe are Class 1-A students, Orimoto, Ebina, and Iroha are in Class 1-B, Saika and the rest of Hayama's posse enter General Studies, and Saki Kawasaki is in Support. For others, Yukino's sister is a successful Pro Hero and U.A. High alumna, and Hiratsuka-sensei works as an Investigative Hero.
• Miraculous: The Phoenix Rises is an interesting case. It's basically if Persona 5 were set in the Miraculous universe, with a falsely accused teen forming a team of supernatural vigilantes to fight social disruption. Of course, another layer is added when it becomes quickly apparent that the cast is largely comprised of expies of the cast of SuperMarioLogan of all things (i.e. Morgan being jeffy, Max being Bowser Jr., etc.).
• In My Huntsman Academia, the heroes and heroes-in-training of My Hero Academia are retooled into Huntsmen and Huntresses-in-training. In addition, the concept of being "Quirkless" is introduced as being "Broken" or a "Moon Child", meaning that one's soul is so weak that they'll never produce an Aura or a Semblance.
• Supah Nario Bros is Naruto if all the characters were mixed with Super Mario Bros. characters (Naruto becomes Nario, Sasuke becomes Princess Toadsuke, Lee becomes Leegi and so on).
• In Necessary to Win, various Saki characters attend the Girls und Panzer schools. For example, the main characters at Oarai Academy have two additional teams- one consisting of the Saki characters from Kiyosumi, and the other consisting of those from Tsuruga. Various characters from each series contrast with each other, such as Maho and Teru's relationships with their respective younger sisters.
• In Neither a Bird nor a Plane, it's Deku!, Izuku Midoriya is a Superman-in-the-making, but the history of My Hero Academia is meshed with the history of DC Comics, resulting in numerous other changes (i.e. Batman and Wonder Woman being active decades before Izuku arrived on Earth, Firestorm is Japanese, ect.) to the established history of both series.
• Paradoxus: The Setting Merge flavor, to be specific. Azeroth and Magix now happen to exist in the same multi-dimensional universe. It's just they are too far apart that, normally, they would've never interacted at all. Here we have Galadwen and Eudora's constant interdimensional traveling and meddling and Queen Daphne's time travel shenanigans, so things are definitely not normal (more like deranged). Now, there are already some canon points that keep this idea within the realm of possibility: there are elves in both franchises, interdimensional traveling is confirmed and used in both of them, and both of them have entities capable of creating entire dimensions (the First Ones for World of Warcraft and the Great Dragon for Winx Club). Though it's worth noting the Great Dragon is not equal to the First Ones, but to the Titans (like Sargeras), which helps to even out the power scales and avoid a Power Creep, Power Seep scenario and allows for the teaming-up plot this crossover roots from.
• An interesting example is Coming Forward, a Paper Mario: The Thousand-Year Door fic by krisetchers. The author got a few chapters in when he realized, purely by coincidence, that his fic had the exact same plot as Final Destination. He decided that the only proper thing to do was to retroactively make it one, even though the fic is in fact a sequel to another fic which has nothing to do with Final Destination. Unfortunately, this means that some really early plot points are forgotten and never mentioned again.
• The Pokémon the Series fanfic Brave New World is basically the anime cast in a version of the Pokémon Mystery Dungeon world (with a dash of Redwall) starring in a Darker and Edgier version of Paper Mario: The Thousand-Year Door.
• The game Pokéthulhu, an Affectionate Parody of both Pokémon and the Cthulhu Mythos, has as its central conceit that there actually is a Pokethulhu cartoon series. In it, the characters are fusions of Pokémon characters and fictional or real people associated with the mythos: the main character is Ash Ketchum/author avatar Randolph Carter, while Team Rocket is Team Eibon, made up of Derleth (named after author/editor/fan hate object August Derleth) and Bloch (named after author Robert Bloch).
• Pony Fantasy VI is a playable romhack of Final Fantasy VI with the cast of My Little Pony: Friendship Is Magic replacing the game's heroes.
• The fan fic Avenging fuses manga in general - Ranma ½ in particular - with Marvel Comics in general and the Mighty Avengers in particular; the Avengers in this universe are based in Tokyo and made up of characters from the Ranma comics. Ranma is both Captain Japan and his spunky female sidekick, Bucky, never seen at the same place at the same time, which Bucky explains by their only having one indestructible shield between them; Akane is Thor; Ukyo is Hawkeye, who is disguised as a man in her superhero identity but is unable to conceal her attraction to Captain Japan; Dr. Tofu and Kasumi are Giant-Man and the Wasp; Ryoga is the Hulk, stumbling onto the testing grounds of the Gamma Bomb when being lost as usual, with his Hulk state being a giant green rampaging boar; Mousse is Daredevil.
• In Angus MacSpon's The Replacement Ranmas, Fusion and Meta Fic mix when the entire cast of Ranma ½ turns up missing on the first day of shooting for a new fic, and the "director" must scramble to replace them with characters from other anime series.
• Renegade takes the Mass Effect setting and replaces Systems Alliance Earth with Command & Conquer: Tiberium's. Changes abound, with a heavily militarized humanity who doesn't align with the Citadel, the Brotherhood of Nod operating in the background, and apparently Garrus being a Spectre, Nihlus surviving Eden Prime, and Kaidan as a Tiberium mutant.
• In Rick and Morty New Drama Adventures crossover between Rick and Morty and Total Drama the fic fuses the universes of the Total Drama series and the Rick and Morty series. The backstories of the characters are blended so that they all grew up in a similar location and attended school with one another.
• Rick and The Loud House is a crossover between Rick and Morty and The Loud House, where Rick is the grandfather of the Loud children instead of Morty and Summer. Each chapter is a cross between each episode of both series^note ; for example, the first chapter is "Left In Another Dimension".
• The Rigel Black Chronicles imports a swathe of characters from the Song of the Lioness into the Harry Potter world, placing them mostly in the Lower Alleys that are essentially an Expy of medieval Tortall. Some are merely equivalents, like Harry's friend Leo, the king of thieves, being a stand-in for George; others are copied name and all, like Rispah Cooper and Marek Swiftknife. The plot also alternates being being primarily inspired by the Song of the Lioness (first and third year) or by HP (second and fourth year).
• A Canon example would be R.O.D the TV, which is a fusion story of Read or Die and Read Or Dream, a manga set in an Alternate Continuity.
• The Remnants of Earth takes the cast of Yu-Gi-Oh! ARC-V puts them into RWBY. It follows the adventures of Team RYGY^note , composed by Reiji, Yuya, Gongenzaka and Yuzu. The story is notable for averting the Stations of the Canon early into the story, slowly combining aspects of Arc V and completely diverging from the original RWBY plot by the time of the main team's initiation which in this setting takes place on the Forever Fall Forest with different objectives and outcomes.
• Various Alternate History works by Rvbomally:
  • In At The Undeath is a fusion of Timeline-191 and the author's own timeline Vivere Militare Est, with the Freedom Party regime using preternatural forces in an attempt to win the Second Great War much like the Axis do in the original VME.
• School Idol Days uses the characters of Love Live! School Idol Project with the plot of School Days. It's about as jarringly brutal as it sounds. Its sequel, School Idol Days S, averts this, as it is based on Love Live! Sunshine!! but has an original story.
• Silly but Killy uses the setting and plot of the first Mass Effect game with the Orks from Warhammer 40,000 replacing humanity and the Systems Alliance.
• Slightly Damned has a Spin-Off comic called The Legend of Buwaro: Soprano of Time by the same author that is an Affectionate Parody of The Legend of Zelda: Ocarina of Time where characters from Slightly Damned play the roles of Zelda characters. Humorously, most of the bosses are played by Thadius.
• Babylon Park is set aboard the Babylon 5 space station, populated by South Park-style versions of the characters.

  "By G'Quan, they've killed Kosh!"
  "You bastards!"

• Star Mares is a fusion of My Little Pony: Friendship Is Magic and Star Wars, positing a potential future of Equestria in which it has become a galaxy-spanning empire recently fallen into tyranny after the fall of the alicorn princesses (who serve the same role as the Jedi in this rendition). Instead of following the canon storyline of the Star Wars films, it relates the misadventures of a motley assortment of background ponies.
• In the Swedish gaming mag Sinkadus, RPG writer Anders Blixt wrote a short story fusing Star Wars and The Lord of the Rings, entitled (in English translation) "Lord of the Rings part IV: A New Hope". It featured Obi-Wan Gandalf and Aragorn Solo leading a bunch of Jawas down into Mordor, eventually encountering "Darth Angmar, the right hand of Emperor Sauron himself!" Who is the daddy of one of the Jawas.
• There is a Let's Play of Super Mario RPG that assigns each character the voice of someone from Family Guy. It was eventually abandoned due 20th Century Studios repeatedly copyright striking the episodes.
• Superwomen of Eva 2: Lone Heir of Krypton: Between Neon Genesis Evangelion and The DCU; Asuka is Power Girl and later Supergirl, Rei is Wonder Girl, other Eva characters have powers of DC superheroes, and several Superman villains show up such like Brainiac or Parasite.
• A Surge of Heroic Intent is a fusion of Fate/stay night and Street Fighter that follows Shirou on the road to become the strongest martial artist in order to protect the people he loves. He's helped by his adoptive older brother and guardian, Luke Sullivan.
• Tangled In Time is a fusion of The Legend of Zelda and Tangled where Ganondorf kidnaps the baby reincarnation of Link after the previous Link dies of old age. Figuring out that reincarnation will mean that killing the infant Link will just another one will be born, he raises Link as his own son. He keeps the young Link unaware of his destiny, despite Link's growing curiosity.
• Justice Society of Japan is a fusion of a number of Anime and Video Game settings (including Tengen Toppa Gurren Lagann, Kingdom Hearts, Code Geass, Fate/stay night, Final Fantasy XIII, Puella Magi Madoka Magica and Neon Genesis Evangelion) with the DCU. Elements from all of these series coexist simultaneously, and while some aspects of the setting are very similar to canon, other elements (such as Shirley being a metahuman with technopathic powers) are added to tie the settings together.
• Thieves Can Be Heroes! is a My Hero Academia and Persona 5 AU in which Izuku never meets All Might and instead becomes the leader of the Phantom Thieves of Hearts.
• This And That has the City actually be apart of the setting of Runterra, with the Outskirts acting as a buffer zone that separates the continent from the rest of the world.
• Advent Cirno, by the doujin circle One Night Stand, is an ongoing Touhou Project take on Final Fantasy VII, with everybody's favorite Baka standing in for Cloud and fighting monsters alongside a Nakama composed of Hong Meiling, and Reisen and Tewi Inaba, along with some other familiar Touhou faces.
• Transposition F: The world of Remnant exists within the Dragon Ball Z universe, with Aura and Semblances revealed to be forms of Ki.
• Universe Falls combines Gravity Falls and Steven Universe into one canon. Several chapters of the fic combine the events of various episodes of the two shows (such as "Legend of the Gobblewonker" and "Giant Woman" becoming "Legend of the Giant Woman", "Dipper vs. Manliness" and "Coach Steven" becoming "Strong in the Real Way", or "Double Dipper" and "Steven and the Stevens" becoming "Copies and Clones").
• Vanishing Act ties together the worlds of Persona and JoJo's Bizarre Adventure. This leads to such developments as Aigis being based off the technology used to create Stroheim's cyborg body, Hifumi Togo being a Stand user whose ability makes her a natural shogi champion, and the main thrust of the fic, Shizuka Joestar becoming a Phantom Thief.
• Vigil takes the Mass Effect setting, adds XCOM: Enemy Unknown's humanity to the setting, and integrates F.E.A.R.'s characters and psionics and Eclipse Phase technology, along with elements of Destiny to the setting, along with some sprinkling of Sid Meier's Alpha Centauri and Terminator as well. The result is a heap of transhumanism, psychic insanity, and ass-kicking with a side of horror.
• War of the Worlds: Global Dispatches, due to the Public Domain status of the two stories it fuses with The War of the Worlds, was actually legitimately published, along with several other unofficial Side Quels.
  • Mars: the Home Front is a crossover with John Carter of Mars wherein Carter tries (and fails) to stop the invasion, and purports that the octopoid Martians of the Wells novel are just one of the many species of Barsoomians.
  • To Mars and Providence is a crossover with Cthulhu Mythos, wherein the local Eldritch Abominations of Mars triggered the martian invasion of Earth when they awoke. They turn out to be humans, and the martians went berserk at seeing that their new digs were loaded with millions of us.
• Mini Mythos by Kenneth Hite, a series of books that fuse the Cthulhu Mythos with popular kiddies' picture books. Where the Deep Ones Are combines Where the Wild Things Are with The Shadow over Innsmouth, Antarctic Express merges The Polar Express and At the Mountains of Madness, and Clifford the Big Red God is a combination of Clifford the Big Red Dog and The Dunwich Horror.
• Worldfall is one between Worldwar and Footfall, featuring a simultaneous invasion of an Earth 20 Minutes into the Future by both the Race and the Fithp.
• Kamen Rider Zi-O: Heisei Hero King combines the worlds of My Hero Academia and Kamen Rider, with Midoriya being the titular Kamen Rider Zi-O.
• Bloodstained Hands And Hearts is a group of oneshots where the cast of Yandere Simulator is put in a Deadly Game ala Danganronpa.
• Justice League of the Rebellion combines The DCU with Code Geass, and while a few DC characters such as Martian Manhunter, Mister Miracle, and Big Barda are present, the cast of Code Geass takes the place of the DC heroes, with Lelouch as Batman, Kallen as Shazam, Rivalz as Superman, Suzaku as Green Lantern, C.C. as Zatanna, Nunnally as Oracle, etc.
• Uncommon Ancestry is a My Hero Academia AU in which the events of Mystery Skulls Animated took place in the pre-Quirk era, with Vivi, Lewis, and Arthur being Inko and Izuku's ancestors. Later chapters also reveal that Shiromori returned to Japan at some point and eventually settled down with a human, becoming the mother of Fumiyo and the grandmother of Ibara.
• While The Devil of UA is predominantly a My Hero Academia story, it takes a lot of elements from the Marvel Universe. Izuku is the setting's equivalent of Daredevil, the Hero Killer Stain is the setting's equivalent of The Punisher and The Hand is a fully-functioning criminal organization, one of its members (Yu Takeyama) being a mole under the guise of a UA student.
• A Hero's Wrath is set thousands of years after the events of Asura's Wrath (presumably during or after the game's epilogue), the Eight Guardian Generals having reincarnated into their descendants, mantra returning and their families rediscovering their mantra affinities somewhere during the emergence of quirks in humanity.
• Fanfiction Flat Dreams fuses Gravity Falls with the novel Flatland by Edwin Abbott, mostly prioritizing the canon of Gravity Falls and changing Flatland to fit better.
• The Devil's in the details:
  • While the fanfic is very much about characters from the Marvel Cinematic Universe, a lot of elements are welded from the X-Men franchise as well, including the Murdock Family's association with Deadpool, the existence of mutants and Xavier's School for Gifted Youngsters.
  • Peter winds up becoming one of the incarnations of Spider-Man to be sucked into Earth-TRN700 by TRN700-Fisk's particle collider, being the only incarnation of Peter who's father is Matt Murdock instead of Richard Parker.
• In Neon Genesis Evangelion Senshi No Michi, the Street Fighter characters live in the Neon Genesis Evangelion world, and some characters of the latter work have replaced some characters of the former one (for example, Shinji has replaced Ryu).
• Demons and Scissors combined two different donghuas, Scissor Seven and White Cat Legend. However, the story is set in an alternate universe where many of the assassins and officials are instead demon hunters while Animals from Scissor Seven are change into demons.
• The Story Shuffle series, due being composed of anthologies gathering stories that include some from the universes of FanOfMostEverything's Fusion Fics, inherits this trope, with the stories set in the Elementals of Harmony universe that blends Magic: The Gathering and My Little Pony: Friendship Is Magic, and especially with Ditzy Doo, a pony that has interacted with both worlds. For example:
• Pokémon Crossing: While most Pokémon/Animal Crossing crossovers are "what if Pokémon characters were Animal Crossing villagers", this one does the opposite i.e. what if Animal Crossing characters were Pokemon trainers. It takes the plot of Pokémon Omega Ruby and Alpha Sapphire but replaces the humans with villagers.
• The Legend of Miraculous, which puts various The Legend of Zelda characters in a modern high school setting based on Miraculous Ladybug, with Link and Zelda as Miraculous holders.
• The Lion, The Witch, and The Fairy's Tail is about the main protagonists of Fairy Tail taking the place of the Pevensie children in arriving and coming to Narnia. It also has two sequels based on Prince Caspian and The Voyage of the Dawn Treader.
• Overtime places characters and settings from Team Fortress 2 into the basic story structure of Undertale.
• An Incognito Query: The The DCU and its heroes exist in the world of Inside Job (2021), with Reagan teaming up with the Question for one of his cases.
• Switch The Colors isn't so much a Crossover of My Hero Academia/inFAMOUS as it is a My Hero Academia fic with elements of inFAMOUS loosely applied. Izuku acts as a setting equivalent to Delsin Rowe who gets his smoke powers from a random, runaway villainess and his Neon Powers from a random mook at the USJ with a backstory similar to Fetch's.
• take me to sea (and never let go) is a One Piece Transplanted Character Fic where the cast of the manga are in the events of Titanic (1997). Notably, rather than a direct retelling of the romance of Rose and Jack, it focuses on Sabo escaping his abusive family and finding his Family of Choice with Ace and Luffy on the Titanic.
• The stage play at the 2010 Discworld Convention was a musical in which Carrot ("DWARF!") and Angua ("WEREWOLF!") find themselves meeting a very strange alternate version of Lord Vetinari, who lives in a mysterious castle with an Igor and Igorina. Yes, it's The Rocky Horror Discworld Show, and it's "official"; Richard O'Brien gave permission, and Terry Pratchett actively encouraged it.
• Uncharted: Drake's Fortune - The Gravity Falls Edition,along with its sequels is, as the title suggests, the Uncharted series retold with Gravity Falls characters in place of those from the original series, with Dipper as Nathan, Ford as Sully and Pacifica as Elena.
• In Rachel The Vampire Slayer, the settings of Animorphs and Buffy the Vampire Slayer'' are merged.
  • Yeerks are replaced with vampires, but these vampires have several Yeerkish aspects (they have to feed every three days—except in this case on blood, they have a substance called Kandrona in their bodies, and they take over a (dead) host body, retaining the host's memories but completely replacing its mind).
  • Other aliens from Animorphs, like Hork-Bajir, Taxxons, and Howlers appear, but are demons from Another Dimension.
  • Elfangor and later Ax take the place of Giles, but are also Andalites in their true form.
• Honoka's Bizarre Adventure: Has the plot and setting of Love Live! School Idol Project mixed with Stands from JoJo's Bizarre Adventure.
• Many works by Lightyearpig have done this. The Marvel Gems Universe inserts characters from the Marvel Universe into Steven Universe, Fooly Falls and Gravity Soul feature Dipper and Mabel Pines interacting with characters from FLCL and Soul Eater, Sly Cooper: Boiling Blood transports Sly Cooper into the Boiling Isles from The Owl House, and Shelluva Boss has the Immediate Murder Professionals from Helluva Boss being hired to kill the Teenage Mutant Ninja Turtles.

---