Biological Mashup



Two or more characters are (for some reason) joined together into one entity. They either have one aggregate personality, or the two fight for control of the common body. They may get control of separate parts of the body, especially if there are multiple heads. Extra points if they are opposites, enemies, or of different species or sex. If the other entity is an animal, this can be a form of Animorphism.

Alternatively, it can be a case of bodily possession by a deceased cast member, or one temporarily without a body.

Can teach a lesson about walking a mile In Another Mans Shoes. It's kind of like an extreme version of Chained Heat, or a Freaky Friday that got stuck halfway through.

Name comes from Mash Up, a sort of track popular with the "remix" crowd in electronic music. Two tracks mixed together, often very different songs, into a coherent whole.

The functional opposite is splitting two aspects of a single being into two separate bodies; see notes on the Evil Twin entry.

Mix and Match Critters (animals made out of different beings) and especially those with Multiple Head Case might suffer from this.

See also Fusion Dance (this is a subtrope). Contrast Shape Shifter Mashup.

Anime and Manga

 * This is how Digimon often evolve, either to Perfect (Ultimate) with other Digimon (Digimon Adventure 02 and the second movie), or to Ultimate (Mega) with their human partners (Digimon Tamers), depending on which series.
 * As well, Chimeramon in Digimon Adventure 02 was created this way, by replicating parts of other Digimon.
 * Stir in Machinedramon and Chimeramon becomes a Japan-only video game's Big Bad, the eventually-godlike space/time-bending Millenniumon. (And since the games reveal that that's who was in the flashback releasing the Dark Spores, leading to Ken becoming evil and eventually creating Chimeramon, Millenniumon is one big Stable Time Loop: he creates himself using Ken.)
 * Speaking of Machinedramon, it sorta fills the trope, as it is made up of parts of other digimon. Granted they are the metal parts of several cyborg digimon, but that left arm is Metalgreymon's.
 * And the games reveal that Cyberdramon came from . And while his being the cause isn't made explicit, it's generally accepted that  is the reason for Cyberdramon's sunny disposition.
 * Wait, what?
 * Birdy the Mighty is about an alien police officer who accidentally killed an Ordinary High School Student when chasing criminals to Earth. She saved his life by fusing with his body, and they can switch forms via a Transformation Sequence.
 * This is kind of an exception to the typical transformation sequence, in that it does not cut away from the scene or involve music or fancy posing. It's more akin to a simple change of clothes, and is executed in a nonchalant fashion, most of the time.
 * Franken Fran, due to the Art Major Biology nature of its science, strays into this territory occasionally.
 * from Claymore ended up fused together in a vegetative state after the latter tried to squeeze the life out of the former. Riful finds them and tries to find a way to awaken them so she can recruit them.
 * In the manga Devilman by Go Nagai, the demons are shape-changing entities, able to possess the human beings by biological mash-up (via teleport). In some cases (as the main character) this possession happens to backfire: the human being "possesses" the demon and gains his powers, but he maintains his/her human identity.
 * A Biological Mashup is the end result of Excel and Hyatt's Freaky Friday experience in the final episode of Excel Saga; Nabeshin is called in to undo it.
 * A Mad Scientist in Fullmetal Alchemist combined people with animals mostly to find out if he could. The results weren't pretty.
 * Later on, other human/animal chimeras are introduced as characters.
 * In the manga, and the anime remake (Brotherhood), there is the case of
 * Also in the manga and the anime remake, Envy's true form,
 * A yeti, riding an ox, while carrying a crane in one hand and a snake in the other, were mashed up when they fell into a spring of Jusenkyo and drowned in Ranma 1/2, creating a unified curse. When a baby is washed and baptized in this spring, he is cursed to become a combination of these.
 * Later in life, this same character willingly augments his chimera-like body by applying a Drowned Octopus curse, which adds tentacles and the ability to shoot ink.
 * In the comedic fantasy anime series Slayers, the character Zelgadis is a mix of human, golem, and demon features. His driving goal in life is finding a cure for his condition, even though it makes him super-strong, super-fast, and immune to most physical damage.
 * Yu-Gi-Oh! has an entire type of card called a "Fusion monster", which results from a fusion of two or three monster cards. Oddly enough, this sometimes results in two monsters fusing into something that looks nothing like either of its components, such as the fusion of Witch of the Black Forest and Lady of Faith (both female magic-users) into Musician King (a male rock-guitar player)! More recently, however, the fusions have started to make more sense. The Elemental Hero monsters are known for this, with most combinations of them having some fusion.
 * The entire premise of Risky Safety is that an angel and a demon are forced to share one body -- there's only room enough for one of them at a time; depending on the emotional state of the people around them, they may suddenly switch places. (Said switch is usually indicated by a sudden puff of smoke enveloping the one, and the other bursting out of it.)
 * In Keroro Gunsou, Keroro and Giroro fused together due to a synchronized swimming routine. (It made a sort of comedic sense at the time.)
 * Nero Chaos of Tsukihime shares his consciousness with 666 beasts. His body, and though he has melded with their minds, he can't actually control the mass very well. Beasts present includes the generic (dogs, wolves, a shark, elephant, crocodile...) and the mythical (a unicorn, some crab-spider thing...)
 * Also the Seventh Scripture's spirit. It's the blend of a (willingly) sacrificed village girl and a dead unicorn's soul. The unicorn had less willpower and was more dead or something, but magically far far stronger, so she spent a while with the unicorn mostly dominant plus sleeping. By this point, she's basically the village girl from before but with weird traits like a horse's tail, hooves and strange ears.
 * Urusei Yatsura once had the teleporter trick with Ataru holding a notebook, which made a copy of his with the notes written all over, and got him stuck in the notebook. Whenever you hit the thing, a paper-thin copy splits off, and Ataru starts selling them.
 * Wapol from One Piece is capable to swallowing multiple people and spitting them out as one, which he did with his minions Chess and Kuramarimo to create "Chessmarimo". Subverted, when Sanji points out that the only thing fused was their clothes, and one is standing on the others back.
 * When a fan asked Oda what it would be like if Wapol fused all of the Straw Hats (which at this time went up to Robin), he replied it would create the creature which possessed Luffy's Straw Hat, Chopper's antlers, Nami's hair situated on it's shoulders, Zoro's swords and haramaki, Sanji's eyebrow situated on top like a strand of hair, Robin's fringe, and Usopp's nose situated on it's left shoulder and is named "Gargon".
 * The Pokémon Special manga has Zapmolcuno, a chimaera resembling a mashup between Articuno, Zapdos, and Moltres, respectively.
 * Also, an episode of the Pokémon involving Gastly had Gastly turn into a chimaera resembling a weird mashup between a Venusaur and a Blastoise as an attempt to fight off Team Rocket's Pokemon.
 * Sakon (And his twin brother Ukon) the villainous member of the Sound Four from Naruto has this as his main power with the ability to fuse their body with each other letting them spring their body parts from any part of the host body. They're most powerful ability however is to fuse their body with an opponent and break down their cells one by one.
 * The Pokémon Special manga has Zapmolcuno, a chimaera resembling a mashup between Articuno, Zapdos, and Moltres, respectively.
 * Also, an episode of the Pokémon involving Gastly had Gastly turn into a chimaera resembling a weird mashup between a Venusaur and a Blastoise as an attempt to fight off Team Rocket's Pokemon.
 * Sakon (And his twin brother Ukon) the villainous member of the Sound Four from Naruto has this as his main power with the ability to fuse their body with each other letting them spring their body parts from any part of the host body. They're most powerful ability however is to fuse their body with an opponent and break down their cells one by one.

Comic Books

 * DCU comic book character B'Wana Beast (and his Legacy Character, Freedom Beast) is a walking example of this trope, in that his magical African potion-induced super power was to fuse any two animals into one.
 * Firestorm, a DC Comics superhero, was born when a student and his teacher were "fused" together in a nuclear accident. The two are able to merge and separate at will, though only Ronald Raymond, the student, has control over the Firestorm form, while Martin Stein, the teacher, only has a ghostly presence during a "fuse". Once the two separate again Stein doesn't even remember what happened while they were joined. Of course, they have no powers whatsoever while separated.
 * One scary example of this trope is Madcoil, a monstrous fusion of sabertooth cat and giant black python. Created when lightning struck the patch of ground where the two were fighting -- ground, which was permeated with leftover elven magic -- this misbegotten Mash-Up beast acted out its insatiable battle-fury on the elven and human tribes of Elf Quest. It fought with fangs, claws, constriction, and (for elves) the capacity to send maddening images of its own horrific "birth" directly into their receptive brains.
 * In the dystopian future shown in the Wild C.A.T.S crossover, Wild C.A.T.s foes The Troika (a human, a Magma Man, and a Killer Robot) had been partially fused together.
 * One of the most horrific moments of the Marvel Transformers comics was when Megatron and Ratchet were mashed together into a single misshapen body.
 * In Grant Morrison's Doom Patrol, Rebis is a fusion of a man, a woman, and an immaterial being called the Negative Spirit.

Fan Works

 * In Vaeru's Fan Fiction Transformers: Juxtaposition, the unfortunate main character is forced to share a body with the arguably even more unfortunate Sideswipe.
 * After Subterranean Animism came out, fusing pairs of characters into one became popular among Touhou fans--which led to this as the logical conclusion. For example, Reon (AKA Saikyou) stuffed thirteen other characters into Kanako, while Persona fan artist Mazeran fused sixteen of the series' Final Bosses and Yukari into one being.

Film

 * The film All of Me.
 * Although not instant, in The Fly, Jeff Goldblum builds a teleporter, and in one personal test accidentally includes a fly in. The resulting DNA fusion turns him into a fly-man monster over the course of the movie.
 * In the original short story, the scientist's initial test of the teleporter causes his cat to disappear. Then the fly-fusion happens; when he tries to reverse it, he only succeeds in adding the cat to the mix.
 * The 1990s version of King Ghidorah was created via this trope. He started out as three cute little critters before being hit by the atomic bomb (Yes, the same atomic bomb that created Godzilla) causing said cute trio of critters to fuse together and mutate into the three-headed dragon we all know and love.
 * In Freaked, a couple of the protagonists, a man and a woman, get turned into a Multiple Head Case.
 * Every single member crew member on the Flying Dutchman in Pirates of the Caribbean is part man and part sea creature, ranging from fish to coral. Sometimes pieces of a ship (like the helm) are thrown in for good measure.
 * This is basically the whole plot of The Human Centipede, albeit in probably the most disgusting way possible.
 * In The Great Muppet Caper, Fozzie and Kermit play twin brother reporters, despite one being a bear and the other a frog. A photograph of the twins' father depicts a green-furred bear with Kermit's keyhole eyes and neck ruff.

Literature

 * In the novel The Gods Themselves by Isaac Asimov the aliens in another dimension merge three into one as a part of their reproductive cycle.
 * In Terry Pratchett and Neil Gaiman's collaborative novel Good Omens, the angel Aziraphale's body is destroyed during a confrontation with an overzealous witch hunter who's mistaken him for a demon when the angel accidentally steps on a pentacle he'd used to communicate with Metatron. As a result, Aziraphale is forced to spend much of the rest of the book sharing a body with a medium.
 * In the Dr. Seuss book I Wish That I Had Duck Feet, the boy eventually wishes himself to be.
 * The Island Of Doctor Moreau had a few Biological Mashup characters, most prominently M'ling, a bear/dog/ox combo, and a hyena/swine man.
 * True History describes several of the creatures that live on the Moon in these terms. You know what that means...
 * In Wayne Barlowe's Barlowe's Inferno, Hell is full of this sort of Body Horror. For example, there are vehicles made up of lots of people who've been mashed together so that they now consist of a big mash of flesh walking around on a collection of human legs.
 * Some of the Remade from China Mieville's Bas-Lag Cycle are this trope, sentenced by the New Crobuzon courts to have parts of animals, or occasionally of human cadavers, magically incorporated into their bodies as a punishment. Occasionally someone has similar modifications done voluntarily, to acquire useful features such as functional gills.
 * Mr. Motley is an even more extreme Biological Mashup, incorporating so many mismatched limbs, eyes, mouths, and miscellaneous appendages into the same freakish body that, when Lin is hired to sculpt a statue of him, she can scarcely imagine how anyone could possibly begin such a task.
 * Happens to Sir Glame and his horse Bill in Plotless, Pointless, Pathetic (a half-book, half-graphic novel, completely-wacky book by Joshua Wright).
 * In the Super Mario Bros-based Nintendo Adventure Book Monster Mix-up, Bowser's son Iggy invents a machine that can fuse random monsters together, creating freakish hybrids.
 * In the Nightside series,  is eventually revealed to be this trope. John and Susie witness its creation from   when they venture into the past.

Live Action TV

 * Adam from Buffy the Vampire Slayer. Big Bad of Season 4.
 * Also Forrest Gates, Adam's Dragon.
 * Numerous examples in Super Sentai and Power Rangers. In some seasons, the Monster of the Week is typically created by composing multiple organisms. There are also several examples of various henchmen being combined to form uber-henchmen.
 * Most examples of monster merging are voluntary, but in Power Rangers in Space, Darkonda is able to forcibly merge with Ecliptor against the latter's will.
 * Plex, the design studio that works on Super Sentai (and Kamen Rider) has a design matrix for making monsters which includes Animal, Plant, and Inorganic elements.
 * In the Scrubs episode "My Princess", Dr. Cox tells his son a vaguely Princess Bride-esque story in which Turk and Carla appear as a two-headed witch known as The Turla.
 * Stargate Atlantis had done this enough times that they do a bit of Lampshade Hanging on the fact that almost all of the major characters have had to share bodies at some point.
 * "Tuvix" (Tuvok plus Neelix) on Star Trek Voyager.
 * One of the main villains in Gerry Anderson's Terrahawks third season was the result of an alien, robotic pregancy. Due to a power failure during the delivery, instead of Cy-star giving birth to twins, what resulted was one being with two distinct personae; a female, sweet natured, lisping personality, and a male, psychotic German-accented personality. Since it had both genders, it was named It-Star.

Tabletop Games

 * The Merging Virus in GURPS: Biotech makes a permanent composite being out of two or more creatures. It's shown as part of a future wedding ceremony.
 * The Ravenloft supplement Children of the Night: The Created describes an unique flesh golem called Gestalt. It was created by a female surgeon who fused together the remains of her two suitors, who'd killed each other in a duel, into a single body and personality.
 * Not really alive, but the Strahd's Malefic Meld spell from the same setting allowed zombie-crafters to get creative, combining various creatures' corpses into Necrological Mash-Ups.
 * The darklord Frantisek Markov and other mad surgeons craft these things the hard way.
 * Phyrexia recognises no species; all organisms can be "compleated", and since they frequently exchange body parts most phyrexians are composed of body parts of many organisms. This is incidently why they can't produce planeswalkers; the spark can't form when there isn't a permanent body to sustain it.

Video Games
"Laverne: Great. Stuck here the rest of my life...listening to Bernard talking and watching Hoagie eat. Mom warned me there'd be days like this."
 * Breath of Fire had several fusion forms your characters could merge into temporarily. Breath of Fire II allowed your characters to merge with "shaman" spirits for various results, some just a minor color change and stat boost, some much more drastic. In both cases, the changes were easily reversible and had little influence on the course of the story.
 * In Castlevania Dawn of Sorrow, before Dmitri dies, the souls of all the monsters he'd absorbed form into a giant mutant which you must fight.
 * Revolver Ocelot loses his arm in Metal Gear Solid in the sequel, he's grafted on the arm of the dead Liquid Snake as a replacement. Liquid's spirit isn't one to give up so easily, and fights with Ocelot for control of his body.
 * By Metal Gear Solid 4 the personalities have reportedly merged to become "Liquid Ocelot" but it turns out that.
 * The Fly was brilliantly spoofed in the climax of the game Day of the Tentacle: three characters use a time machine at the same time (Dr. Fred even mentions the movie by name as they did this), and end up fused into a three-headed, six-armed freak; at the end of the game, however, it is revealed that they weren't mashed up at all, but instead during the rough ride through time two characters had ended up inside the third one's shirt -- given their appearance after they stepped out of the time machine, they had assumed they'd been fused together.


 * The fangame Mushroom Kingdom Fusion has the Fusionist, a scientist working for the Big Bad. He makes a lot of Biological Mash Ups. The true final boss is also one of these.
 * The ghost(s) of the elven sisters who first fought the King of Shadows in Neverwinter Nights 2. As the sisters describe the fight in their own words, 'went in 6, came out 1, went in 6, came out 1...'
 * The final boss of Tron 2.0 is a monstrosity that.
 * Mother 3. The biological chimeras that the player encounters are bizarre amalgamations of ordinary animals created by the Big Bad because the normal creatures "suck". Examples include the Monkalrus, Ostrelephant, and Cattlesnake. You don't get points for guessing what they're combinations of.
 * The final boss of Golden Sun is the two primary antagonists fused into a two-headed dragon.
 * Samus from Metroid could count. Being a human, she had to be infused with Chozo blood so she could survive on Chozo planets. Then at the start of Fusion, she receives a vaccine to save her from the X Parasites; said vaccine is made from Metroid DNA, which altered her genes and made her part Metroid as well. And if you want to get technical, she could be considered part X parasite after absorbing so many of the little monsters, and then when you think about all of the species whose DNA was absorbed by the X...
 * Legion from the PS game Shadowman. Naturally, he quotes off I Am Legion.
 * The Mooks in Ribbit are standard versions of this, like a snake with porcupine quills. The title character (apparently the first to be made) is a variant, with a rabbit's head and a frog's head joined by their necks, lacking a torso or limbs. (Note that Ribbit is not a Multiple Head Case, referring to itself as "I.")
 * Vampire: The Masquerade Bloodlines has a rather disturbing example of this trope in the sewer levels, where the large, spider like enemies are in fact a group of women mashed together. On an even more disturbing note, one of these women appeared to have been pregnant. Bloody Tzmisce...

Web Comics

 * Ysengrin from Gunnerkrigg Court is a wolf-man with trees for arms. He used to be a normal ; his current body was given to him by a trickster-god.
 * The Coyote simply gave him the power to control trees. He decided to morph them into a sort of biological powered armor.
 * Magellan starts with the character Brian Lonsdale fusing himself with his pet dog Elvis, producing the biologically mashed-up (and generally messed-up) Brelvis Lonsdog. And no, the process isn't reversible. In a later story, while attempting to find a cure, Brian's father replicates the process with !
 * The "Meanwhile in the Dimension of Pain (or wherever)" guest strips for Sluggy Freelance conclude with the crowning absurdity of several of the demon characters mainly used only in those stories being accidentally fused into one grotesque blob of a creature.
 * Lespuko-chimera characters from El Goonish Shive can acquire and combine forms.
 * Sprites in Homestuck can be prototyped twice. In the kid's session, each sprite was prototyped with something human and something non-human, with the exception of Rose's (which was prototyped with an Eldritch Princess doll and her dead cat's corpse. In the troll's session this is mostly avoided, with the exception of Aradia second-tier prototyping herself with her frog sprite. So far, the sprites that have suffered the worst from this trope have been Jade's sprite (a combination of ) and Jane's (prototyped by   throwing   into the kernelsprite).

Web Original

 * In The Gamers Alliance, a dragon, an archdemon and a mage join together into a single entity which becomes the Godslayer.

Western Animation
"K'nuck-Jack: Finally we are one."
 * In Transformers: Beast Wars, the Vok fused Tigatron and Airazor into the vastly powerful Tigerhawk and used him as their envoy, and there was an entire subgroup created from malfunctioning stasis pods called "Fuzors", who had aspects of two different real-world animals (many of whom didn't appear on the show). Examples include Silverbolt (wolf/eagle), Quickstrike (scorpion/cobra), Torca (bull/whale), and Injector (hornet/lionfish).
 * Speaking of Transformers, this is done in a much more horrifying way in the Marvel comics. Let's just say this cover wasn't a typical comic cover mislead. And the caption at the top couldn't be more literal.
 * In the Futurama episode "Put Your Head On My Shoulders", Fry's body is critically damaged in an accident, and his head is temporarily grafted onto Amy's body while his own is being repaired. The situation is complicated by the fact that the two had been dating, but just before the accident Fry had been planning to break up with Amy.
 * In Men in Black: The Series, rogue agent Alpha is one of these in his every appearance, using a Cosmic Integrator to fuse body parts from various aliens to himself. He believes it "improves" him, but really it just makes it clear how nuts he is.
 * In one episode of AAAHH!!! Real Monsters, as punishment for disrupting class, The Gromble combined Krumm and Ickis into "Krickiss" and waited until they got sick of being "stuck" with each other.
 * Kevin 11 from Ben 10 absorbs the energy from Ben's Omnitrix and, in a fit of screaming rage, mutates into an amalgam of Ben's various forms. The different parts thus stuck together also give him Combo Platter Powers.
 * One episode of Buzz Lightyear of Star Command pairs off most of the organic characters one by one into blobs. (You can even see most of Team Lightyear all mushed up together in two images on this site.)
 * Cat Dog, whose protagonists are... well, you guessed it.
 * In one episode of Aladdin, Aladdin and Mozenrath's spirits are both trapped in Aladdin's body after a botched Grand Theft Me.
 * Cleveland and Quagmire get fused together after an accidental nuclear war brought on by Y2K in the Family Guy episode "Da Boom". Peter initially calls them "Clevmire", but Quagmire insists on "Quagland".
 * In Coldstone's second appearance on Gargoyles, he is retconned into being made from parts of three gargoyles that died in the attack on Castle Wyvern, which also causes him to get two extra personalities, one female and one evil.
 * Word of God says it was the intention all along.
 * It's an understandable mistake, given Coldstone's coloring. He's largely supposed to be seen exactly as Demona described him -- "cold stone brought to life" -- and thus should have been a shade of gray. However, the artists gave him the coloration of the personality that fanon now knows as Othello, making it seem like he's the only gargoyle from whom Coldstone is physically formed.
 * In the new He-Man and The Masters of The Universe, Skeletor punishes two mercenaries named Tuvar and Baddhra for ruining a plan with their bickering by fusing them into one body with two heads: this series' origin of the villain Two-Bad.
 * And from the same producers as BLOSC, Kim Possible's DNAmy does this to various critters as a central villain idiom, to duplicate her favoite plush toys, the hybridized "Cuddle Buddies".
 * In The Secret Saturdays episode "Ghost in the Machine", the main character Zak ends up fusing with both Komodo (a Komodo dragon) and Fisk (a 'gorilla-cat') after discovering a government project created to produce cryptid super-soldiers.
 * In the South Park episode "A Ladder to Heaven", Cartman accidentally drinks Kenny's ashes, and along with them his soul, with the result that Kenny ends up sharing Cartman's body, in a parody of Star Trek III the Search For Spock.
 * Also from Southpark, there is Man Bear Pig, the half-man, half-bear and half-pig (sic) creature that Al Gore wants to warn the world about. He is completely cereal about the threat.
 * Another episode a lot earlier when dentists think a giant half-squirrel half chicken was the culprit of missing teeth and money.
 * One episode of, of all things, SpongeBob SquarePants uses this.
 * In the second Teenage Mutant Ninja Turtles series, two different members of the rogues gallery, Drako and the Ultimate Ninja, temporarily get merged together into a half-dragon, half-human body.
 * The finale of the Terra Story Arc in Teen Titans involved the Titans facing a monster created by merging together three of the series' recurring villains, Cinderblock, Overload and Plasmus. They later benefited from a Snap Back.
 * The main characters in Disney's cartoon series (and associated plush toy line) The Wuzzles are all beings exhibiting the biology of two different animals; including Bumblelion (Bumblebee/Lion), Hoppapotamus (Hippo/Rabbit) and Mooseal (Moose/Seal). (It's possible they were at least the partial inspiration for the Cuddle Buddies mentioned above.)
 * Toxic Crusaders had surf-dude delivery boy "Fender" and mad scientist "Dr. Bender" accidentally fuse together forming the new hero... Headbanger.
 * Junkyard also qualifies: a homeless man who takes shelter with a junkyard dog whose kennel was covered in toxic waste dump. Add one bolt of lightning, and their molecules merged into a humanoid dog.
 * Exo Squad's Neosapiens created Neo Warriors, Lego Genetics combinations of animal and Neo DNA, as cannon fodder. Later, they combined the best attributes from several species to create the smart and tough Neo Lords.
 * Not a biological mash-up, but in one episode of Adventures of Sonic the Hedgehog, Dr. Robotnik's bungling robot lackeys Scratch and Grounder are badly damaged, and Robotnik puts them back together from the few parts left over as one two-headed robot, which he dubs "Scrounder".
 * Clone High: "I am a Hunkicorn. Half hummingbird, half donkey, and half unicorn."
 * In Dragon Tales, Zak and Weezy are a two-headed "Odd Couple" dragon, Zak being the uptight male half and Weezy being the exuberant female half. They do split into separate bodies, but decide to rejoin by the end of the episode.
 * In the Marvelous Misadventures of Flapjack episode "Gone Wishin", when K'nuckles tells Flapjack that mermaid tears can make wishes come true, Flapjack imagines himself and K'nuckles merged together:


 * In Wild Kratts, a poor octopus gets a hold of Martin and Chris's creature power suits, which give them the ability to become any animal. It malfunctions and just starts adding species instead of changing it, so when the brothers run into the octo-walrus Chris is convinced they've discovered a new species, but when they get to octo-walrus-shark-bowhead-whale-mackerel, they're just terrified.
 * In the Phineas and Ferb episode "Canderemy", Candace and Jeremy are literally joined at the hip after being exposed to a stray shot from Dr. Doofenshmirtz's Combine-inator. Later, the doctor combines with his robot manservant Norm to become "Normenshmirtz", and at the end, the titular boys get combined into a single (highly unnerving) entity.