Involuntary Shapeshifting / Western Animation

• A somewhat common occurrence on Aladdin: The Series:
  • "Sneeze the Day": Genie comes down with a case of Power Incontinence where his sneezes cause random magical effects to anything nearby, covering his nose when he sneezes instead caused him to transform randomly (and uncomfortably).
  • "Do The Rat Thing": Jasmine's boasting and Iago's sarcasm while the former is holding a magic mirror inadvertently transforms them into a rat and a lizard, respectively. They spend the rest of the episode trying to get back to the palace to Genie can turn them back.
  • "Eye of the Beholder": Mirage curses Jasmine, who begins a Slow Transformation into a snake-woman so poisonous that nobody can even touch her without risking death.
  • "Shark Treatment": Saleen the siren turns Aladdin, bit by bit, into a mindless shark under her command.
  • "When Chaos Comes Calling": While Jasmine and Aladdin were hosting a party, the primal entity known as Chaos "livens it up" by giving Iago a human head and transforming the other guests randomly: one was given a donkey's head and could only bray, a husband and wife pair were given the lower halves of kangaroos and couldn't stop hopping, one was turned into a humanoid hippo, and another husband and wife pair were transformed into a whale and a vase of flowers. Chaos transforms most of them back after a few minutes (except for the hippo-man), but later in the episode the first husband and wife pair are once again transformed into half-kangaroos and forced to hop away, with no indication they were ever changed back.
• In Alienators: Evolution Continues, as a result of him volunteering as a human guinea pig for finding a cure against the Genus, Wayne Grey undergoes random mutations (including growing extra limbs, splitting into more copies of himself, or becoming animal-like in appearance) every time there is a high concentration of alien cells in the surroundings. In one particular episode where the aliens grow out of control and briefly take over the whole world, he kicks into overdrive and explodes into a pink goo. In the final episode, the whole team gets sent on the Moon. Makes you wonder what the hell a two-headed spacesuit was doing in a space shuttle.
• In The Amazing World of Gumball, Penny Fitzgerald turns out to be a shapeshifter whose form underneath her peanut shell is based on her self-image and possibly other emotions, from a rabbit, to a dragon, to a form that looks somewhat similar to how she was with the shell still on. She's rather self-conscious about it, which indirectly leads to her mimicking the way people describe her (or that she thinks they're describing her).
• American Dragon: Jake Long: In one episode Jake begins to shift randomly from human to dragon, sometimes one body part at a time. Application of "liquid plot" does this once, revealing his identity to his worst human enemy.
• In the cartoon based on the film Attack of the Killer Tomatoes!, Tara Boomdeay (originally a tomato granted a human form) turns back into a tomato when she touches salt. She turns back into a human girl after having pepper sprinkled on her and she sneezes.
• In the Batman: The Animated Series episode "Feat of Clay: Part 2", Batman manages to guilt Clayface into doing this by showing him clips of all the roles he's played in the past. As Clayface remembers each one, he's turned into that character uncontrollably, until it literally turns into a type of torture: Clayface begging Batman to stop, but unable to until he's exhausted and supposedly capturable. It's debatable whether Batman was trying to get this reaction, since he'd already seen Clayface involuntarily start shifting into Batman upon their first meeting. His look of surprise suggests that he may not have expected such a strong reaction. Of course, given the way the episode ends, it's equally possible that Hagen was simply playing to his audience: Batman. He was an actor, after all....
• Beetlejuice, from both cartoon series of the same name, changes constantly based on any wordplay to be found in his dialogue, apparently by force of habit. In "The Neitherworld's Least Wanted", a coalition of bad guys he's faced exploits this by tricking him into saying "I'm coming apart at the seams", and then scattering his body parts when he literally falls apart.
• While usually a voluntary shapeshifter, albeit frequently not into the form he wanted, the Ben 10: Omniverse episode "The Frogs of War" involves Ben accidentally activating the Omnitrix's randomizer function, which causes him to randomly transform into different aliens.
• Similarly, Bonkers in one episode caught "literalitis", a disease which caused him to take the form of any idiom he heard. In another episode his first partner, Detective Lucky Piquel, caught "toon flu" and turned into a little three-inch high character when he sneezed.
• Agent 57 from Danger Mouse discloses his random shapeshifting as having unstable molecules (he ran into a molecular fragmenter with his tea trolley). Whenever he sneezes, his electrolytes become imbalanced and causes him to change forms.
• Early in Danny Phantom, Danny has trouble controlling his powers and sometimes goes partially ghost at random. Leads to his pants falling down at one point, memorable for a line that followed later that episode. The beginning of the episode "Identity Crisis" really emphasized this with Danny's shape shifting abilities. Very amusing.
• Darkwing Duck gets zapped with an experimental Transformation Ray in one episode, and gains the power to turn into anyone he looks at. Downside is, he can't turn it off. And this is only one of many episodes of Darkwing Duck with this trope as the premise.
• The Fairly OddParents!:
  • One episode has Cosmo shapeshifting against his will due to his "Fegiggly Gland" working wrong.
  • In another episode Timmy wishes to be Cosmo and Wanda's godparent. As a fairy, Timmy can never get his transformations right. When he finally transforms into a fish, he doesn't give himself gills.
• In the episode "Dexter's Date", Freakazoid! is zapped at a television station and cannot change back into Dexter Douglas, leaving his date waiting — and turning instead into random celebrities. (Fortunately, he turns into a blue Louis Armstrong just in time for his lines in the huge splashy "Hello Dolly" musical number parody. Don't ask.) The weird part is he always has his own voice, except for the Louis Armstrong bit.
  • In the 2-part Origins Episode “The Chip”, Dexter initially had this problem after becoming Freakazoid, frequently switching between the two identities due to his powers being unstable. It isn’t until he yells that he’s “freaking out” during a particularly stressful moment that he masters the transformation.
• Most Gargoyles turn to stone during the daytime; Demona turns into a human instead, thanks to a spell cast on her by Puck. She can't induce or repress this transformation; it happens every day when the sun rises, and reverses when the sun sets. Demona hates her human form (like she hates everything human), but that doesn't mean she's not perfectly willing to take advantage of it when it comes in handy for getting what she wants. It also doesn't help that it's a Painful Transformation.
• Kaeloo's Mr. Cat is one of these, his transformations into random objects usually brought upon by Kaeloo beating the stuffing out of him.
• Looney Tunes:
  • Chuck Jones' bizarre late-entry "I was a Teenage Thumb" has a wizard with the hiccups who transforms into different random things with each "hic" — a lamppost, a touring car, a hot-air balloon...
  • In the short "Transylvania 6-5000" Bugs Bunny encounters the vampire Count Bloodcount. Bugs is able to force the Count to transform into a bat by saying "abra cadabra" and back to humanoid form by saying "hocus-pocus" Later in the cartoon Bugs induces bizarre partial transformations by mixing up the words, i.e. "abraca-pocus", "hocus cadabra", "Newport News", and "Walla Walla, Washington".
• A TV series titled Monster by Mistake! features a main character who is a young boy named Warren. Warren turns into a blue monster whenever he sneezes.
• In the Ned's Newt episode "New Improved Zippo", Newton suffers this after the company that makes Zippo Newt Food (the stuff that usually allows him to change his size, talk and gives him his shapeshifting abilities) changes its formula.
• In the Al Brodax Popeye cartoon "The Wiffle Bird's Revenge," the Wiffle Bird casts a spell on Wimpy, making him turn into a werewolf when he says the word "hamburger."
• In Project G.e.e.K.e.R., Geeker is a genetic shape-shifter who can't control his abilities; he sometimes collapses into a puddle when he panics; in one episode, he sleep-walked through the city for several nights — in Kaiju form.
• Punky Brewster
  • In "Growing Pain," Glomer is allergic to pepperoni pizza. When he sneezes, it causes growth spurts. The flowers from Margaux's parade float causes him to reduce size a little, but Punky isn't listening to him explain it. She's focused on her own float.
  • In "Little Orphan Punky,", Punky asks Glomer for a "nice disguise", which, because of a cold, he mishears as "mice disguise", turning Punky, Margaux, Cherie, and Alan into mice against their will, just in time for an angry guard dog to show up. He's unable to change them back (due to the same cold), though it does wear off on its own after a few minutes.
  • "Fish Story" is a case of Be Careful What You Wish For. Punky did ask Glomer to help her with her mermaid costume, and at first she was excited at the new "costume" he made for her. But when she couldn't remove it and realized he'd actually transformed her into a real mermaid (and he was unable to change her back), she was very angry with him, and the rest of the episode's plot involves trying to change her back.
• Dingo of Sonic Underground had the ability of transforming into virtually any other object or person, though these are invariably orange in color. His transformations are completely under control...of his partner Sleet, that is, not himself.
• Steven Universe is half-Gem, an ageless race with Voluntary Shapeshifting powers that he has yet to master, which has caused him problems on occasion:
  • In "Cat Fingers", his first attempt at shapeshifting goes awry and he gradually turns into a writhing mass of cats.
  • "So Many Birthdays" demonstrates that he's literally as old as he feels; in other words, if he feels old, he is old. He ends up nearly aging himself to death via Power Incontinence.
  • "Steven's Birthday" takes it in the opposite direction; Steven's literally as young as he feels, which leads him to a troubling revelation: physically, he hasn't actually aged in years. He later attempts to shapeshift himself into the "correct" age, which backfires due to the strain it places on his body, reverting him to infancy.
• Steven Universe: Future: In the penultimate episode, after spending the series having a crisis of identity and dealing with lingering PTSD from everything he's experienced during his childhood, Steven accidentally shatters Jasper (she gets better) and has a breakdown when he intentionally tries to shatter White Diamond in the midst of an episode. Steven becomes so terrified of himself that he views himself as a monster and transforms into a literal one the size of a building. Because he sees himself as a monster, he does not retain sentience and attacks everything in sight, with White Diamond even describing him as "not Steven" and Blue Diamond comparing his state to the Corrupted Gems.
• Teen Titans (2003):
  • Beast Boy (who is normally a Voluntary Shapeshifter) has had occasional mishaps, such as a series of transformations that occur during a sneezing fit from the common cold. Or the episode where Raven learns how to use her powers to force him to change into another creature against his will.
  • Plasmus is what a very unfortunate man uncontrollably turns into whenever he's awake. He's kept comatose most of the time, and when awoken barely has time to be horrified about what's going to happen before he transforms into a destructive Blob Monster he seemingly has no control over.
• Teenage Mutant Ninja Turtles (1987): During the last two seasons, this begins happening to the turtles themselves: at inopportune moments, they transform into monstrous, mindless forms. At the same time, the turtles make a new ally in Carter, who also suffers from his own kind of involuntary shapeshifting, albeit one in which he keeps control of his faculties.
• On The Thing, while Benjy's transformations into the Thing are usually voluntary, in the episode "To Thing or Not To Thing", a treatment meant to turn Benjy back into the adult Ben Grimm instead has him spending all day transforming back and forth into the Thing uncontrollably, before ultimately failing.
• Transformers:
  • Various Transformers have had occasions where they lose control of their transformations between robot and alternate modes. Most commonly, this happens when they're hit hard enough, or as a reflex when one is startled. Beast Wars is rather fond of the former.
  • Word of God has it that, in the metaseries, Primus, Unicron, and the Original 13 Transformers's bodies automatically change to fit the physics of whatever universal stream they enter (similar in effect to a Fisher Kingdom, but caused by themselves, not the universe they enter). Primus and Unicron stop there, but the other 13 change further to fit the specific idiosyncrasies of the local Transformers. For example, when The Fallen is in the G1 universe, he looks blocky, and in the live action movie universe he looks more thin, lithe, and pointy. Also, in G1 he is on fire, while in the movie universe, due to physics, he is merely glowing red-hot.
• The main character of Turbo Teen shapeshifts into a talking car when his body temperature rises, almost always at inopportune times. Making him cold reverts him to his human form, which also frequently happens at inopportune times.

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