Whenever characters have Voluntary Shapeshifting powers or undergo Forced Transformation, the altered forms are usually an exclusive one-person deal. Only one individual can use a particular transformation or transformations.
However, the Shapeshifting characters may be able to pass the transformations on to other people while losing the transformations for themselves. Perhaps they found the transformations personally inconvenient, or perhaps the recipients are deemed more deserving of the alternate forms. Perhaps a Power Parasite desires the unique form. Passing on the transformations may involve some magical form of Energy Donation reliant on Equivalent Exchange, or at least giving a unique Transformation Trinket to the other person. Whatever the reason or method, the result is that one person now has a transformation that formerly belonged to someone else.
If an undesirable form is involved, expect the recipient to try to find the original donor to force them to take it back. In other cases, a beneficial transformation may be stolen by the other character as a type of Power Copying where the unwilling donor loses the transformation. Oftentimes, the alternate forms had already been passed down through a Chain of Deals; if the transformations are distinct enough, they may even be treated as Legacy Characters.
Powers as Programs may sometimes be involved. Contrast with Viral Transformation and Werebeast Tropes, which involve transformations that are spread and multiplied among multiple people without the original donors losing them. See also Body Surf.
- Ayakashi Triangle: After Matsuri changes from a boy-turned-girl to a boy and a girl, the first theory is that the sex-changing spell was removed from Matsuri and turned into an ayakashi Opposite-Sex Clone with the same memories. Later on, it's revealed to be an inversion: girl Matsuri is the original human, but her original male form was taken away to create a boy Matsuri clone.
- Naruto: Normally, absorbing too much of "nature energy" would turn one into a frog, and then a stone statue. Naruto eventually manages to "weaponize" this when he fights one of Pain's bodies, which specializes in Energy Absorption; when he grabs Naruto's body, the latter starts meditating to gather nature energy, causing said Pain body to absorb Naruto's nature-energy-infused chakra as well, morphing his body into having frog features and then turning him into stone.
- GG Bond: Originally GG Bond had all the powers of transformation for himself, being able to transform into a tiger, a bear, a crane, an ape, and a deer. Eventually, all the transformations got transferred to GG Bond's fellow teammates, with GG Bond keeping only the tiger one.
- One Iznogoud story has a foreign prince cursed into a frog, and kissing the frog would transfer the curse to the kisser. At some point the curse was copied instead of transferred (no explanation for was given in the comic, but the Animated Adaptation had it happen when the frog kisses someone instead of the reverse).
- One of Phil Foglio's XXXenophile stories features a protagonist who'd been forcibly transformed into a centaur, and the mage that cast the spell was killed before he could be forced to remove it. When her boyfriend tries to assure her that she is still beautiful (by having sex with her), she goes back to her human form ... but the boyfriend is now a centaur. They do solve the problem... and we see the boyfriend's traumatized-looking horse with six legs.
- Dungeon Keeper Ami: Ami's Sailor Mercury transformation can be applied to whoever she possesses, but she only has enough magical power to sustain five of them at once, so if she's used them all and wants to give someone else her power, she has to de-transform one of the holders and apply the transformation to someone else.
- Some legends of the rougarou (a Cajun variant of werewolves) say that drawing blood from an attacking rougarou will return the creature to normal but pass the curse onto you.
- Princesses of the Pizza Parlor: In Grandmothers and Other Fearsome Encounters, when Flora is about to undergo involuntary Transflormation due to a spell-casting accident, an enemy steals the spell, and undergoes that transformation instead.
- The Unicorn Chronicles: The Last Hunt reveals that Elihu, creator of Luster, was turned into The Dimblethum as punishment. His friend Fallon later willingly takes the transformation on himself so that Elihu can try to heal the Axis Mundi; he succeeds, but it costs him his life.
- During the fourth season of Agents of S.H.I.E.L.D., the Ghost Rider, whose usual host is Robbie Reyes, displays the ability to transfer itself to other hosts during the course of the season, and it's how Robbie originally gained the power of the Ghost Rider, through contact with its previous host Johnny Blaze. During the season finale, the Rider possesses Coulson, allowing him to completely destroy Aida, the Big Bad of the season in question.
- The Star Trek: Voyager episode "Vis à Vis" combines this with Body Surf. A criminal has the ability to swap bodies with anyone he/she touches, and he/she (we never learn the character's original gender) periodically does this to strap the unwilling recipients with the consequences of his/her actions. Initially interacting with the crew of Voyager as a man named Steth, the criminal swaps with Tom Paris (who becomes Steth) and later with Captain Janeway (who becomes Paris). The real Paris teams up with the real Steth (stuck as a woman named Daelen) to capture the criminal and restore everyone to their original bodies, with the real Steth subsequently vowing to follow the trail of all the people the criminal swapped with.
- In Pathfinder, most beneficial polymorph spells can only be cast on oneself, but the brown-fur transmuter has the extremely rare ability to apply them to its allies, on top of making the forms more powerful than usual.
- One Tockington sidequest in Dragon Quest XI sees the party visit the town of Moonahan from Dragon Quest II. In the original II, the Princess of Moonbrooke was transformed into a dog by Hargon's forces and had to wait for the two Princes to find a mirror that could change her back. In the Tockington quest, however, the mysterious character altering the stories of the previous Dragon Quest worlds made it where the Princess was able to change back prematurely at the expense of everyone else in Moonahan becoming dogs. She asks the Luminary to find the necessary item that will turn her into a dog again so the people of Moonahan can be uncursed.
- Starting with the arcade games and eventually appearing in Mario Kart Wii, the Mario Kart series has an item called the Thunder Cloud which shrinks the holder after a few seconds. To keep this from happening, the player who gets the Thunder Cloud from an Item Box must bump into another racer, who will get shrunken instead.
- Late into Tales of Xillia 2, it's revealed that Chromatus users who use their powers for too long will eventually become Divergence Catalysts, effectively killing them. However, the protagonist, Ludger Kresnik, isn't transforming into one himself because he was holding onto Elle Mel Marta when he first activated his powers, and her special Key of Kresnik abilities allowed her to take on the transformation in his stead, meaning she herself will die soon.
- Trials of Mana: At one point, your party gets trapped on a ghost ship, where a ghost fanatic got cursed and turned into a ghost himself. Unfortunately, he transfers the curse to one of your party members, rendering them unusable for the duration of the dungeon. The other two party members understandably keep their distance once they find out about how the curse works. Once Gova is destroyed by the remaining two party members, Shade dispels the curse for you.
- One Danny Phantom episode involves a cursed amulet necklace that changes the wearer into a fierce dragon whenever they get mad. Initially in the possession of a ghost princess mad that her mother won't let her go to a ball, it gets worn by Paulina Sanchez, who gets mad that a trendy clothing item is out of stock, and then Sam Manson, who gets mad at Paulina's shallowness.
- When the Monkey King is unearthed in Jackie Chan Adventures, he's in the form of an inanimate wooden puppet, with instructions to pull his leg. Those who do so — Jackie in one episode, and a hapless bystander in another — are turned into lifeless puppets themselves. The transformation can be undone by either having the Monkey King pull the puppet's leg in return, or by turning him back into a puppet through other magical means.
- In one storyline of Spider-Man: The Animated Series, Spider-Man is suffering from a mutation disease, making him transform into a monstrous Man-Spider sometimes. Vulture, who steals youth from other people to keep young, doesn't know about this when he steals Spider-Man's youth. He asks Curt Connors for help, but Connors double-crosses the Vulture, modifying his equipment to return Spider-Man's youth to him, but not the Man-Spider transformation.