History Main / PainfulTransformation

* ''Website/SCPFoundation'', [[http://www.scp-wiki.net/scp-1575 SCP-1575 ("Venus Statue")]]. When an animal drinks water that has passed through SCP-1575, it mutates into a human being. If it survives the process, the former animal describes it as being extremely painful. The water doesn't lose its potency after ingestion either; the SCP has to check animals for internal and external parasites after there was a half-mutated flea and a human-faced tapeworm screaming as it burst out of a dog's belly.

* ''Wiki/SCPFoundation'', [[http://www.scp-wiki.net/scp-1575 SCP-1575 ("Venus Statue")]]. When an animal drinks water that has passed through SCP-1575, it mutates into a human being. If it survives the process, the former animal describes it as being extremely painful. The water doesn't lose its potency after ingestion either; the SCP has to check animals for internal and external parasites after there was a half-mutated flea and a human-faced tapeworm screaming as it burst out of a dog's belly.

* ''ComicBook/WonderWoman'': The way people react when [[ReforgedIntoAMinion being turned into]] Circe's [[BalefulPolymorph Beastiamorphs]] indicates that it is a very painful and horrific experience.
** ''ComicBook/WonderWoman1942'': Maj. Keith Griggs collapse and screaming transformation when Circe nabs him is a good example of just how unpleasant being transformed into one of Circe's loyal mooks can be.

* In the climax of ''WesternAnimation/AtlantisTheLostEmpire'', Milo slashes the villain, [[spoiler:Rourke]], across the arm with a piece of the magic Atlantean crystal, leaving a spot of pure crystal on his arm...which [[BalefulPolymorph instantly starts spreading]] across his entire body. BodyToJewel has never looked so painful.

** 3rd Edition has a sourcebook which expands on the rules and abilities of wizards and sorcerors called ''Tome and Blood''. It gives the Prestige Class of "The Acolyte of the Skin", which is gained by summoning the essence of a fiend and binding it to your flesh. The [[http://stat8.blog.ru/lr/0810eba6e00aefdca4ca43fe1e1215dd illustration]] is [[{{Squick}} not pretty]].

* In the ''WebVideo/{{Smosh}}'' [[https://www.youtube.com/watch?v=3OOoE0CHtlk video about the bad parts of Heaven,]] in the sprouting wings segment, the angel wings come outrather bloody and painful looking.

[[folder:Anime & Manga]]
* No transformation fits this trope better than Tetsuo's mutation in ''Manga/{{Akira}}'' which also may be one of the most over-the-top examples of BodyHorror ever depicted.
* A lot of this in ''VideoGame/ArcTheLad'', [[spoiler:as for chimera transformations]]. ''A lot.''
* Transforming into a Hollow in ''Manga/{{Bleach}}'' seems to be an agonizing process, if the Pluses' reactions to it are to go by.
* In ''Anime/BloodPlus'', the transition from human to chiropteran is not pleasant. For example, when Saya is forced to turn her little brother to save his life after her PsychopathicManchild of a [[EvilTwin twin sister]] nearly kills him, Riku just convulses and screams his head off before falling into a coma for several days.
* Mamoru Kusanagi from ''Manga/BlueSeed'' bleeds green blood when he brings out his arm blades.
* In ''Manga/CaseClosed'', Shinichi's transformation to Conan is painful each time he goes through it. Understandable, as his body was literally undergoing apoptosis. To give some idea, he constantly describes his de-aging as feeling like his [[BodyHorror bones are melting]] and begins to sweat profusely while clutching the left side of his chest, [[FridgeHorror like he's having a heart attack]]. The first time he re-aged, he ended up bedridden and thought he was actually ''dying''. Both types of transformation also cause him to burn up so much that his body is literally smoking (or maybe ''steaming'') as it happens. Poor guy.
* In ''Manga/DevilMan'', when a person is infected with a demonic spirit they scream in pain as they are transformed into demons.
* ''Franchise/{{Digimon}}'':
** ''Anime/DigimonFrontier'': The Beast Spirit Evolutions have a painful yell as the characters evolve. Kouji in particular will sometimes suffer pain and/or weakness after ''de''-transforming, whether the transformation was painful or not, leading to {{Fanwank}} about what just what it is that makes it so hard on Kouji alone. Adding to this, Kouji and Kouichi most likely go through the most painful transformations of them all. This may be because the Beast Spirits bend their bones, flesh, and bodies to match their evolution. Everyone else is rather human-shaped while these two have to suffer a complete bone re-structure.
** Although not quite as much, the evolution sequences in ''Anime/DigimonTamers'' show the Digimon in slight pain as their skin is peeled off.
* ''Manga/DNAngel'':
** Hiwatari's transformation into Krad is very painful, one of the factors being the fact that he usually fights it quite hard. Contrast with Daisuke's relatively easy transformation in to Dark, only experiencing pain for the first time and [[spoiler:when he grows his own wings in the final episodes.]]
** In the manga, Daisuke feels pain when transforming [[spoiler:after Risa was kidnapped off the Farris Wheel because he transformed with anger, not love]]. This could also explain why transforming is so painful for Satoshi. [[spoiler:The one time he did transform with little-to-no pain was after diving to save Risa when she fell off the tower, transforming out of "love" (according to some fans).]]
* ''Anime/DragonBallZ'':
** Freeza's transformations in particular tended to involve a lot of screaming and incredibly painful-looking contortions.
** Buu's de-transformation from Super Buu to Kid Buu consisted of nothing ''but'' standing around and screaming for a very long time, but that may have been less physical pain and more that he was devolving from a fairly intelligent AxCrazy to a mindless OmnicidalManiac.
** Ditto for Goku's first-time Super Saiyan 1 and 3 transformations. Goku's transformation into [=SSJ3=] however is more exhausting than painful though.
** The Legendary Super Saiyan's first transformation of Broly (in [[Anime/DragonBallZBrolyTheLegendarySuperSaiyan his first movie]]) and Kale (in ''Anime/DragonBallSuper'') seems to be extremely painful.
*** For Broly (DBS), the Wrath State causes him a great deal of physical pain due to his power erupting and his body expanding in muscle mass. He can be seen clutching his head in pain, and though it seems like it, the constant screaming is not entirely because he's angry, but due to the constant pain he's in. It only gets worse when Broly turns Super Saiyan, where he loses all trace of sanity.
* In ''Anime/ErgoProxy'', Ergo Proxy's first couple of on-screen transformations involve lots of painful screaming. The transition seems to become smoother later on.
* Various instances in ''Anime/EtoRangers'':
** While it's not explored much in the show, Hols's SuperMode, changing from an anthropomorphic bull into a much stronger feral one, is implied to cause him a lot of pain and distress in his ImageSong. Understandable, considering that his TransformationTrinket -- [[BullSeeingRed the color red]] -- is, as he points out in the song, [[BlessedWithSuck completely unavoidable]].
** When [[BrainwashedAndCrazy under Jyuken the Gatekeeper's control]], Pochiro, Pakaracchi, and Tart ''begin'' to come to their senses, only for Jyuken to stop it in its tracks by forcing the former two into hulking monstrosities. Tart [[SubvertedTrope successfully fights the transformation process]], but judging from her cringing and inability to move, it certainly wasn't an easy fight, and she almost lost.
** [[spoiler:Chocolat's transformation into Nyanma]]. Evil energy pulses around her, her eyes dilate, her muscles tighten, and she screams in agony the whole time.
* ''Anime/EurekaSeven'': Eureka's wings growing from her back is not a pleasant experience.
* Tsubasa's first transformation into ''Anime/Figure17TsubasaAndHikaru'' seems to cause her pain for unknown reasons, although as she's presented floating in some kind of CyberSpace environment, it might be purely mental.
* In ''Manga/FullmetalAlchemist'', [[spoiler:Ling's transformation into Greed and Bradley's transformation into Wrath]] both have the transformees look like they're being ''torn apart'' and [[spoiler:Bradley]] describes it as a continuous cycle of dying and being revived until he pulls through.
* The title haibane of ''Anime/HaibaneRenmei'' are born looking like normal humans, until their wings grow during their first night in the town. Having a pair of wings explode out from one's shoulder blades is about as painful as it sounds.
* Not sure if it counts as a transformation, but in ''Anime/HellGirl'' season 3, Yuzuki after [[spoiler:being possessed by Ai]] goes through a surreal sequence where she convulses and screams as this egg-thing comes out of her back. The poor girl has to go through this every time [[spoiler:Ai is contracted to send someone to Hell]].
* A slightly different version in ''Anime/HowlsMovingCastle'' - Howl can turn into a giant bird-thing pretty easily. It's changing ''back'' that hurts.
* Late in ''Manga/InuYasha'', the title character is forced to use a [[MineralMacGuffin Jewel Shard]] on the Tetsusaiga to give him a power boost; however, the jewel becomes corrupted and forces him to transform into a [[AxeCrazy full]] [[SuperPoweredEvilSide demon]]. Given how much he is screaming, it's safe to assume the forced transformation is pretty damn painful.
* When Akatsuki from ''Anime/LogHorizon'' uses the shapeshifting potion to edit her character, the transformation is accompanied by bursts of light, sickening cracking sounds and a lot of screaming.
* ''Franchise/LyricalNanoha'':
** Vivio's forced transformation [[spoiler:into her [[OvernightAgeUp Sankt Kaiser form]]]] in ''Anime/MagicalGirlLyricalNanohaStrikers'' involved a lot of convulsing and screaming in pain.
** Hayate's similar transformation at the end of ''Anime/MagicalGirlLyricalNanohaAs'' appears similarly painful, but as her body is at this point being controlled by an A.I., it seems unlikely that she felt it.
* In ''Anime/MahouNoMakoChan'', [[https://www.youtube.com/watch?v=drOHCAlII0Q&feature=player_embedded#at=132 Mako's transformation]] from mermaid to human is pretty disturbing, complete with DerangedAnimation, Mako screaming, and the ocean and moon turning red.
* When the title character of ''Manga/{{Naruto}}'' releases his Demon Fox power at the [[FourIsDeath four tails]] level, his skin peels off before burning into ash, and blood covers his entire body to form the Kyuubi's body. Also, he loses consciousness because of the injuries to his body, and the Demon Fox takes control of it. Changing back is also incredibly painful as he temporarily ''has no skin''. Even the lesser forms are painful to an extent. The chakra is poisonous to Naruto and constantly burns his skin, only the accelerated healing it grants preventing him from succumbing to the damage.
* In ''Manga/NegimaMagisterNegiMagi'', the chronic [[ImHavingSoulPains soul pains]] that Negi suffers ever since learning [[DangerousForbiddenTechnique Magia Erebea]] are a symptom of him being [[spoiler:''turned into a demon'' by overuse of the technique]].
* Jarbilong in ''Manhwa/{{Priest}}'' uses the body of a former vicar to take physical form in his battle against Ivan Isaacs. The poor sod screams ''a lot'' while his ribs stretch out of his chest and a new head grows out of his back.
* [[DarkMagicalGirl Princess Kraehe]] of ''Anime/PrincessTutu'' goes through a painful, involuntary transformation to unlock her SuperpoweredEvilSide.
* Evangelion Unit 02's [[BerserkMode Beast Mode]] in ''Anime/RebuildOfEvangelion 2.0'' requires of a painful realignment of the spine held in place by 10 pylons, all fed back to the pilot via [[EmpathicWeapon Empathic Link]]. [[spoiler:Mari]] was very visibly affected by this.
* While it is inconsistently portrayed (at least in the manga), the more extreme renditions of Chise's transformations into [[PersonofMassDestruction the Ultimate Weapon]] in ''Manga/{{Saikano}}'' are agonizingly painful for her.
* In ''Anime/{{S cry ed}}'', Kazuma and eventually [[spoiler:Ryuho, Martin Zigmarl and Straight Cougar]] damage their bodies when they go into their alter forms. Usually, the scars appear where the armor does. For example Kazuma gets scars on his arm, then on his face and even part of his hair starts to change. By the end of the series, he doesn't even open his right eye unless he's in his alter form (which he might possibly not even ''have'' outside of his alter form). They look pretty scary during the last fight.
* Tiara and Leon's transformations in ''Anime/ShamanicPrincess''. At least those work like they're supposed to -- it gets worse when [[spoiler:her best friend]] forces the transformation.
* The victims of Stigma's rings in ''Manga/{{Shy}}'' are forced to relive their darkest emotions which materialize in the form of dark crystals, making them look like japanese oni. They also lose most of their self-control, leading to them attempting suicide or going on rampages.
* Valgaav from ''LightNovel/{{Slayers}} TRY'' is capable of a partial transformation into his dragon form. The transformation appears so painful to him that he never manages to transform fully.
* Even though Ichika's later transformations in ''Anime/UtaKata'' are perhaps not physically painful as such (although she tends to become nauseous), they are ''extremely'' unwanted and emotionally scarring.
* ''Franchise/YuGiOh'':
** In ''Anime/YuGiOhGX'', [[spoiler:Yubel was [[WasOnceAMan originally a young child]] and a friend of a prince who would become Judai in a later life. He ([[AmbiguousGender or maybe she, it's hard to tell)]] volunteered to become Judai's spiritual guardian, and became the demonic Duel Spirit that was first seen in the third season. The process -- which seemed to combine alchemy with surgery -- was only seen briefly, but given what we did see -- and hear -- it likely was ''very'' painful for Yubel.]]
** ''Anime/YuGiOhArcV'': Whenever any of the four boys Awaken, they are often mentally in pain, their bodies heat up and their chests tighten up.
[[/folder]]

[[folder:Fan Works]]
* ''Fanfic/AbraxasHrodvitnon'': [[ZigZaggingTrope Zig-zagged]] and somewhat {{defied|Trope}} during Vivienne Graham's {{Metamorphosis}} inside San's decapitated head. She's kept comatose throughout her months-long gradual transformation, but still, in the first chapter, her spine lengthening causes so much agony that it gets through to her unconscious mind and San has to sedate her further. Later after her rebirth, Vivienne (who at this point has been through a ''lot'' of physical punishment) screams in utter agony when San's new head on her back rapidly develops its jaws.
* When John becomes water in ''Fanfic/WithStringsAttached'', it's not physically painful, but it's incredibly mentally disturbing.
** Similarly, when George becomes an air elemental in ''Fanfic/TheKeysStandAlone: The Soft World'', he feels like he's going to fly apart at any moment.
* In ''Franchise/TheLegendOfZelda'' fanfic ''[[Fanfic/BoundDestiniesTrilogy Blood and Spirit]]'', [[spoiler:Link is forced to suffer this gradually throughout the plot of the story, due to his corruption at Majora's hands in a variety of ways, which is slowly turning him into another copy of the Fierce Deity. On the physical side, almost every time the hero enters into a spell of corruption, the chest wound he received in the battle against the original Fierce Deity that started the corruption in the first place reopens, causing him considerable pain. But even worse than that is the mental/emotional side of things. Not only does Majora constantly torment him and threaten him inside his own head, but the demon also vows that it will force Link himself to kill Zelda and everyone else he cares about once the hero has fully succumbed to the corruption and even goes as far to say that this has always been the hero's destiny since he was born. It's no wonder that both Majora and the corruption are revealed as two of the only things Link truly fears.]]
* Chrysalis' corruption by Discord in ''Fanfic/DiariesOfAMadman'' was extremely painful for no reason other than Discord found it funny. The first time someone uses Nav's [[GenderBender gender stones]] is also very painful.
* In ''Fanfic/AHairyProblem'', the first werewolf transformation after somepony contracts lycanthropy is very painful, though the pain resides after subsequent transformations to simply being uncomfortable or nonexistant. Applejack (and Fair Vista in Sable Loam's flashback) experience this, and then Apple Bloom and Lightning Dust go through this as well in ''Fanfic/AHairierProblemRiseOfTheFurball''. Applejack has the misfortune to go through this TWICE as her lycanthropy apparently went into regression at the conclusion of ''A Hairy Problem'' and Raspberry's dark magic outburst at her trial seems to have brought it back.
* In the ''Manga/InuYasha'' ContinuationFic ''Fanfic/BeyondTomorrow'', [[OriginalCharacter Hanyuu]] endures this while undergoing her first [[BroughtDownToNormal transformation into a full-blooded human]], just sitting there crying and groaning in agony while Kagome tries to comfort and distract her from the pain. Inu-Yasha, standing guard outside their hut, reflects that his own first human transformation was much the same. However, it's explicitly stated that only the ''first'' transformation is painful.
* Jade Chan's transformation in ''Fanfic/{{Webwork}}'' into a [[spoiler: Jorogumo/ Oni hybrid]] is so painful that the author placed warning around sections the reader may want to avoid. and at one point she has to be placed into a coma for months on end while [[spoiler: her skin melts off and her bones dissolve while she grows an exo-skeleton]] so to avoid months of pain.
* In the first story of the ''Fanfic/FacingTheFutureSeries'', Sam's ghost transformation is similar to Danny's. In fact, the author says Jazz will never forget Sam's chilling scream.
* In ''Fanfic/RiskItAll'', Ren's powers, particularly when boosting physical stats like Strength, tend to modify his body in relation to the points he accrued. When learning skills, this leads to a pinching feeling in his brain as he becomes an InstantExpert of whatever he just learned. But after going viral and dumping a lot of points into his stats overall, the sudden change makes him feel like he's dying and every muscle goes taut as he gasps for air. The sensation is so excruciating that he blacks out afterward, waking up the following morning.
* In ''Fanfic/TheBridge'', Monster X's transformation into Kaizer Ghidorah is excruciating as his bones and muscles rearrange themselves and wings burst from his back in a shower of blood.
* In ''Fanfic/StreetSharksRedux'', the canon effects of gene slamming (see Western Animation) are made even worse. The protagonists feel sick, sore, and confused almost immediately after waking up, which only escalates as they try to figure out just what happened to them. When John starts changing, he's in too much pain to move and basically collapses on the ground. It's later mentioned that the brothers had relatively painless and simple transformations and that adults experienced mutations even ''worse''.
* ''Fanfic/TriptychContinuum'': In ''Triptych'', Experienced by ''her'', ''constantly''. Whatever went wrong in the ascension attempt resulted in perpetual cyclical shifting between the three main pony races, moving from pegasus to unicorn to earth pony to pegasus again, and so on through the cycle. Rarity believes the wing bones are ''breaking'' rather than simply being reabsorbed. Whether this is true is unknown, but ''she'' is in endless, unrelenting agony.
* In ''Fanfic/{{Raindancer}}'', Izuku's first experience with his Quirk began when pressure began to build inside of him to the point that he felt like he was going to explode. He then began to uncontrollably spew an endless amount of water from within his own body, drowning from within as he looked as his mother with tears in his eyes. Then his entire body quivered as it began completely turning into water and collapsed into a puddle. Luckily, he was perfectly alright afterwards and all subsequent transformations are quick and painless, but the event was terrifying for a four-year-old to experience.
* In ''Fanfic/{{Delusions}}'', transforming into an alicorn is painful. Celestia and Luna's ascensions hurt even more than Twilight's (which involved wings growing and a height change) did because they were originally mules. Celestia can't even describe the pain.
* In ''Fanfic/AmazingFantasy'', the spider bite that gives Izuku his powers wracks his entire body with pain, gives him intense nausea, and makes him sweat profusely while feeling [[ImColdSoCold deathly cold]] at the same time. He ends up blacking out and going into a coma for two days after being rushed to the hospital.
* ''Fanfic/SoYouArentAsHumanAsYouThoughtYouWere'' John goes through this when the Chameleon Arc begins to wear off. Though it mostly manifests as sensory overload.
* In ''Fanfic/YouCallThatACostume'', when the Rainbooms are afflicted by a BecomingTheCostume spell, it's implied that it was painful for most of them.
[[/folder]]

[[folder:Films -- Live-Action]]
* In Makodap's short film ''11'', the main character Peter Baxter attempts to flee from a luxury resort without paying his bill. He is tricked by the company and is painfully transformed into an attractive young woman. The [[https://www.youtube.com/watch?v=606fx-y6puQ painfulness of the transformation]] is intense with Peter screaming in agony, as bones break and reform. The company intends to get their money somehow, and have plans for Peter, or Nikki as he will be known as.
* The first time Dr. Curt Connors changes into the Lizard in ''Film/TheAmazingSpiderMan'', he is ''not'' having a good time.
* ''Film/AnAmericanWerewolfInLondon'' popularized the idea of lycanthropic transformation as physically excruciating with its famous TransformationSequence.
* In ''Film/BeyondSherwoodForest'', Alina's transformation into a dragon is shown to cause her considerable pain.
* The first transformation sequence in ''Film/TheCompanyOfWolves'', wherein a werewolf, having disappeared for several years, flies into a rage over being forgotten by his lover. He begins to tear his own face off before his flesh splits open by itself, revealing the intricate details of the human anatomy for a few moments before the muscles and bones begin to twist into the shape of a wolf's, the visceral display traumatizing the woman's children all the while. Then his former lover's husband returns to the house and beheads him. His head goes flying into a vat of milk, then resurfaces as a human head, his blood staining the milk pink. Delicious!
** A later transformation sequence is taken from folklore: A jilted witch curses her ex-lover's entire wedding party to become wolves until she changes them back. Considering that the wolf-forms erupt through the victims' mouths, and the sheer volume of screaming involved -- yeah, not pleasant.
* In a variant from ''Film/{{Creepshow}}'', Jordy's gradual transformation into a mass of green filamentous space-vegetation isn't exactly painful, but it ''itches'' so badly that he can't resist immersing himself in water to relieve his discomfort, even knowing that this will only accelerate the process.
* Using the shape-shift drug [[TabletopGame/Warhammer40000 polymorphine]] doesn't look like much fun if agent Lechias' face in ''Film/{{Damnatus}}'' is anything to go by; not to mention that just to ''start'' the process you have to stab yourself in the stomach with a big friggin' needle.
* In ''Film/DogSoldiers'', the transformation into a werewolf is apparently very painful, as the unfortunate lycanthrope-to-come begins screaming and grunting as they stagger around the room, tripping over random objects, as fur begins to grow and they generally display more wolf-like characteristics as the change continues, growling instead of crying for example.
* Vlad's first step to becoming a vampire after he drinks the Elder Vampire's blood in ''Film/DraculaUntold''? His body shuts down and dies.
* ''Film/TheFly1986'':
** After a ''slow, humiliating and painful'' metamorphosis from a healthy man into a sickly decaying half-insect wretch, Jeff Goldblum's gruesome and heartbreaking final transformation into "Brundlefly" has his skin peel off in chunks, his joints crack audibly into reverse position, and his skull '''split open''' to reveal its new insect shape.
** In the sequel, his son Martin's transformation averts this. Most of the transformation takes place in a cocoon. Martin is then reborn as a powerful insectoid man-beast who takes bloody revenge on the company that treated him like a lab-rat his entire life.
* ''Film/GhostRider2007'': Johnny Blaze's first transformation into the Ghost Rider has his skin burning and melting off. He goes beyond the point of screaming in pain and winds up laughing maniacally before the process finishes. Subsequent transformations are instantaneous and seemingly painless -- unless the Ghost Rider just doesn't acknowledge pain.
* ''Film/GIJoeTheRiseOfCobra'': [[spoiler:Destro getting his metal face.]]
* ''Film/HellboundHellraiserII'' reveals that Cenobites are created from certain poor souls who solve the Lemarchand Configuration. Becoming one is as agonizing as it looks, largely because it involves your skin being split and metal inserted into your flesh. In the opening flashback Elliot Spencer's transformation into Pinhead has him screaming as the iconic pins are put in his skull. Much later in present day, Julia betrays Dr. Channard by feeding him to [[EldritchAbomination Leviathan, the Cenobites' master]]. Cue the doctor screaming as razor wire is wrapped around his head, weird fluid is shot into his veins, and some kind of weird tendril-like appendage fuses to his cranium.
* In ''Film/HocusPocus'', we don't actually see Thackeray Binks' transformation into a cat, but we can ''hear'' his body changing shape, as well as the poor guy screaming as it happens. It doesn't sound comfortable ''at all''.
* Sebastian becoming invisible in ''Film/HollowMan'', as well as making the previous test subject visible again.
* In ''Film/{{Innerspace}}'', Tuck uses a procedure on Jack to reshape his facial features to disguise him. He warns him beforehand that it will hurt, and it certainly does. (And hurts even worse when it wears off prematurely and his face snaps back to normal.)
* The poor title character of the dark and edgy ''Film/KamenRider'' {{deconstruction}} film ''Film/ShinKamenRiderPrologue'' suffers from this. Rather than simply having the "armor" appear over his body, Shin's body actually changes, distorts and morphs into the Shin Kamen Rider. This is only done twice in the film and is extremely painful for the guy (also destroying his clothing); specific super-creepy examples include his eyes [[RedEyesTakeWarning turning bright red]], his forehead splitting open four ways at once and then his antennae erupting out of it, and his jaw ''splitting in half''. They had to tone the costume down a bit for his appearance in ''Series/KamenRiderDecade'', and even then, he was still pretty scary looking.
* ''Film/TheLeagueOfExtraordinaryGentlemen'', Hyde-to-Jekyll. Hyde is more than twice Jekyll's size, considerably bulkier in terms of muscle mass. Ouch. The transformation also seems to be physically exhausting, as Jekyll is shown red-faced, sweating, and panting the first time he changes back.
* ''Franchise/MarvelCinematicUniverse'':
** In ''Film/CaptainAmericaTheFirstAvenger'', two of these occur.
*** Firstly, Johann Schmidt: he is shown injecting himself with the unfinished SuperSerum in a flashback; fire then burns around him and it cuts to his face clearly in pain and screaming, turning into the Red Skull.
*** Secondly, Steve Rogers. During Project Rebirth, he has the serum and Vita-Rays pumped through his body -- about half way through the procedure it becomes a lot more intense and he is heard screaming from within the pod. The scientists immediately get up to shut down the machine -- but Steve yells at them to keep going despite the pain (becoming a ''[[HeroicBuild freaking man mountain]]'' when it's done).
** ''Film/TheIncredibleHulk2008'' shows a different take on the classic Hulk-out; Here, Banner's transformation into The Hulk is ''massively'' unsynchronized, with body parts changing at different paces. In one scene, the bones in Bruce's shoulder grow faster than the rest, leaving his skin grotesquely distended for a brief moment.
** In ''Film/TheAvengers2012'', the Hulk's first transformation looks excruciating and takes a long time, because Banner is fighting it the whole time. The second time, he transforms intentionally and it only takes one smooth second, with no thrashing or screaming.
* ''Film/TheMask'': The first time Stanley puts on the mask. All the times it occurs later it's off-screen, for a good reason. Though thankfully it’s a lot less painful coming off and even better The Mask is a genuinely insane but a sweet, kind hearted polite person who other than shoving exhaust pipes into the bottoms of the mechanics is pretty much harmless and wants fun most of the time. The Mask Pressbook has this to an extreme in their test images of Jim Carrey turning into the Mask. One of them looks like it was borrowed from ''The Howling'' or ''American Werewolf in London''. There are pictures of that on [[http://www.jimcarreyonline.com/forum/viewtopic.php?t=8492 Jim Carrey Online]].
* ''Franchise/ANightmareOnElmStreet'':
** In ''Film/ANightmareOnElmStreetPart2FreddysRevenge'', Freddy takes over Jesse's body by messily transforming it into his own shape. This includes blades growing out of Jesse's fingers, his skin peeling off, and Freddy ripping open and bursting out of his chest. Jesse is howling in visible agony the entire time.
** In ''Film/ANightmareOnElmStreet4TheDreamMaster'', Freddy Krueger transforms [[spoiler:Debbie]] into a cockroach by breaking off her arms and then [[TearOffYourFace forcing her to rip her face off]] to reveal the insect parts underneath.
* ''Film/TheNuttyProfessor1996'': Sherman's transformation into Buddy Love is excruciating, and it causes him to pass out. [[spoiler:It is {{deconstructed|Trope}} when Jason, Sherman's assistant, discovers that the weight loss formula that Love plans to ingest is lethal.]]
* In ''Film/OzTheGreatAndPowerful'', poor [[spoiler:Theodora]] undergoes this when tricked into consuming a sort of PsychoSerum. It's both a case of physical and mental pain, and the final result is [[spoiler:The Wicked Witch of the West]].
* In ''Film/RomasantaTheWerewolfHunt'', Romasanta's transformation from wolf to man is accompanied by the sound of snapping bones and howls of pain.
* Ron Howard wanted something like this originally for the bathtub scene in ''Film/{{Splash}}'' where Madison the mermaid turns into her mermaid form in the bath, but he feared that it would ruin the appeal of the character. The part where her lower torso bubbles and turns scaly is a bit eerie, but Madison seems pretty relaxed about it.
* [[spoiler:John Connor's]] transformation into the T-3000 in ''Film/TerminatorGenisys''. The infection that transforms him is nanomachine-based, and introduced through ''his mouth'' when [[spoiler:the T-5000]] grabs him. The initial scene shows glowing matter penetrating into [[spoiler:Connor's]] head from around his mouth. A later flashback shows him mid-transformation, his flesh and bone being gradually turned into machines, all while he writhes in agony and the nanomachines make sickening crunching and buzzing noises. For a split second, his entire head is shown beginning to be converted.
* In ''Film/{{Troll}}'', when Torok injects Peter with his ring to turn him into one of his minions, he turns bright green with slime oozing from cuts on his body while screaming in agony the whole time, morphing into a cocoon which cracks open. Out pops a little monster with Peter's facial features and spider legs.
* The ''Film/Underworld2003'' universe has a variation of this ({{implied|Trope}} in the films, outright stated in the {{Novelization}} of the first movie). The first transformation into a [[OurWerewolvesAreDifferent Lycan]] is ''extremely'' painful, but it becomes much less so over time, and each individual adapts. In ''Underworld: Awakening'', Quint Lane has undergone experiments to transform him into a [[CanisMajor super-Lycan]], but an apparent side effect of the treatments seems to be that unlike most other Lycans, he can't transform seamlessly; even simply [[PartialTransformation morphing one hand into a Lycan claw]] has him visibly wincing and groaning in pain.
* Bavmorda's "You're all pigs!" spell in ''Film/{{Willow}}'' cannot be described as pleasant. Every victim screams in pain and wriggles on the ground as they transform.
* In ''Film/TheWolfman2010'', turning into a werewolf involves a lot of snapping bones and blood from the mouth.

[[folder:Literature]]
* In ''Literature/{{Animorphs}}'' it's often noted that morphing doesn't hurt...but really seems like it ''should,'' given how the characters can feel their bones crunching around as it happens.
** It is low-key BodyHorror, though, as most people (Cassie being one exception) can't really control how the process works, causing parts of you to change at random and inconsistent rates. There is also a bit of the psychological element, too, depending on [[TheMindIsAPlaythingOfTheBody what kind of instincts]] they get when they're done.
** One book has Rachel note that the transformation is usually painless, but this time is an exception, until she figures out it actually is someone kneeing her in the back (they're demorphing in a tight spot).
* Roger's [[HenshinHero transformation]] in ''Behemoth'' is accompanied by BloodFromEveryOrifice, which coagulates and becomes InstantArmor and generally happens in response to grievous bodily harm. Comes with dangerous hypotension afterward.
* OlderThanPrint: In Myth/IrishMythology, "The Boyhood Deeds of Cuchulainn" from the ''Literature/TheCattleRaidOfCooley'' describes Cuchulainn's Riastarthae (warp-spasm) as a very painful-sounding transformation.
* In Tansy Rayner Roberts's ''Creature Court'' series, the characters can usually shift into animal, Lord or chimaera form pretty easily. However, if they've had recent contact with [[KryptoniteFactor skysilver]], the transformation becomes a ''lot'' more unpleasant. Naturally, this happens to Ashiol at every given opportunity.
* All werewolves in ''Literature/DarkestPowers'' first transform during puberty. Derek's was shown to be extremely painful.
* Inferno XXIV of ''Literature/TheDivineComedy'' gives a vivid account of thievish shades transforming into snakes and lizards, and vice versa. The transformation is treated like a rape, a topic so horrid Dante only explicitly mentions it in the context of Lucifer's rebellion against Heaven.
* ''Literature/DrFranklinsIsland'' by Ann Halam, two girls get turned into a fish and a bird. The narrator describes this as being really uncomfortable. The bird-girl's sternum goes clean through the skin of her chest, [[BodyHorror not a pretty picture]]. The transformation back is much easier on both of them, but the fish-girl is sick and uneasy for much of it and the bird-girl spends five days in something like a coma.
* In ''Literature/GauntsGhosts'', the [[spoiler:rogue]] Inquisitor Handro Rime has a collection of agents known collectively as the Sirkle. They all share the same face, to act as doubles for the Inquisitor, and it is [[spoiler: implied the two scenes that he dies in are in fact his doubles]]. It's revealed that they use a special form of internal mechanism to alter the tension and position of muscles and even ''fracture and reset bone''. It is repeatedly noted that it is incredibly painful, requires immense focus to maintain one face, and a moment of surprise causes them to reveal their true face. And whenever they transform, it occurs with a [[NauseaFuel horrifying crunch of bone]]. [[spoiler:Cue HeroKiller moments.]]
* ''Literature/HarryPotter'':
** Werewolf transformations are described as being excruciatingly painful. Animagi and Metamorphmagi, however, easily transform at will without the slightest discomfort because it is a magical skill instead of a disease.
** The description of Polyjuice Potion transformation includes the phrase ''bubbling skin''... creepy and painful.
** This trope happens when characters have to drink skelegrow to regrow lost skeletal parts (Harry had to do so thanks to a botched attempt at mending his arm when it was broken during a Quidditch match), and it is stated that the process is extremely painful and would require the entire night at the infirmary.
* ''Literature/JourneyToChaos'':
** The transformation caused by mana mutation is always painful because it reshapes the victim's body at random. All the while the brain is receiving signals of what's happening, including ones that it doesn't know how to interpret.
** ''Literature/LoomingShadow'' has many examples of how painful this can be. Patrick Lumberson lay halfway between human and fitzger with {{mana}} sparking on him like electricity. Kallen encounters a monster in the midst of transforming and mistakes its screams of pain for threatening hisses. [[spoiler: The reader sees into Eric's mind when it is shorting out from a mana explosion.]]
** Bladi Conversion is a [[TheDarkArts a Forbidden Technique]], in part, ''because'' it is painful. The convertor replaces the genetic information in the converted's blood by overwriting it, in effect, replacing the converted's parents, biologically speaking. [[spoiler: Zettai]] describes it as ''the'' most painful thing she's ever experienced.
* A gradual version in ''Literature/KeysToTheKingdom'': as [[spoiler: Arthur's flesh and blood]] become more saturated with magic, he is shown to scream in agony as his bones and muscles shift and grow to make him taller, more handsome, and "more perfect".
* When in ''Literature/LoyalEnemies'' Rest asks, how does werewolf transformation feel, DeadpanSnarker Shelena sums it:
-->'''Shelena:''' So, you're interested, what a human feels, when they're violently crumpled, turned inside out and stuffed with hair? Or a beast, in reverse order?
* Werewolf transformations in the ''Literature/MercyThompson'' series are quite painful and are often rather prolonged as well, with some of them taking around fifteen minutes or so. As werewolves are already rather short-tempered, it's generally a good idea to tread carefully around a recently-changed werewolf until they get themselves back under control.
** Averted with Mercy herself -- as a walker, a type of Native American shapeshifter, switching between her coyote form and human is painless and nearly instantaneous. Charles Cornick, a werewolf who inherited some powers from his Native American mother, still feels pain when he shifts, but his transformations are much faster and smoother than normal.
** One werewolf is kidnapped and attempts to change while under the influence of copious amounts of drugs, which means she gets stuck halfway through. She starts leaking bodily fluids before managing to finish the change with the help of the almost-full moon.
* ''Literature/MonsterHunterInternational'': Werewolf transformations always hurt since the body's very skeletal structure is transforming, much less the other body changes, though the pain get easier to handle (or at least acclimate to) with experience. Also played with, in that according to Earl Harbinger [[spoiler:speaking from experience]], pain itself can often be a catalyst for InvoluntaryShapeshifting as a werewolf can instinctively try to go beast when hurt (usually to try and better murder whatever caused it), and it takes training to ''only'' transform on command (at least until the full moon comes out).
* Werewolves in ''Literature/TheParasolProtectorate'' face this problem when shifting between human and wolf forms. The physical pain never lessens, but older wolves get better at hiding it, culminating in [[BadassBookworm Professor Lyall]] who is the most graceful shifter anyone in the cast has ever seen. The initial metamorphosis is also generally painful, but only because it normally involves [[ThisIsGonnaSuck an Alpha werewolf tearing you a new one]].
* Paelen from Kate O'Hearn's ''Pegasus'' series can stretch his bones almost indefinitely. While this is a useful skill in a series where the protagonists keep getting captured, it also hurts like crazy.
* ''Literature/PercyJacksonAndTheOlympians'': While the scene following Percy's transformation into a Guinea pig is oddly funny, the way he describes the actual process hardly sounds fun. Like [[Film/OzTheGreatAndPowerful an above example]], he's tricked into drinking a potion and says it felt like sudden, burning heat in his stomach, unnatural physical changes, and then terror, because he had no idea what was happening.
* In ''Literature/RiversOfLondon'', the disguise-spell ''dissimulo'' molds flesh and bone into a new appearance, and subverts this trope by dulling the resulting pain ... at least, until the spell shuts down. Then, the pain of having ''most of your face collapse'' is the least of your problems.
* In ''The Shattered World'', were-folk transformations become more and more painful the older they get.
* ''Literature/TheStrangeCaseOfDrJekyllAndMrHyde'': When Dr. Jekyll drank his potion, "the most racking pangs succeeded: a grinding in the bones, deadly nausea, and a horror of the spirit that cannot be exceeded at the hour of birth or death."
* ''Literature/{{Twilight}}'' vampire transformations are described as three straight days of burning, terrible pain. But you can choose not to scream if you really don't want to.
* If the werewolves of ''Literature/UncommonAnimals'' initiate the change, it's very painful. So much so, that the human mind can black out, leaving a frightened wolf. Speaker initiated changes do not hurt at all.
* ''Literature/TheVampireChronicles'' transformation includes the body painfully rejecting digested food and fluids.

[[folder:Live-Action TV]]
* Just like in the movie, the Ghost Rider transformation in ''Series/AgentsOfShield'' is not at all fun; the person undergoing it often winces in pain as it starts up. Since it involves their entire face burning off, it's easy to see why.
* ''Series/{{Being Human|UK}}'':
** George's [[https://www.youtube.com/watch?v=ZpeJbN2IDy8 werewolf transformation]] is agony. During the transformation, a werewolf has every organ in his body simultaneously stop: heart attack, kidney failure, liver failure, and so on. Meanwhile his bones are cracking and twisting against each other, and his skin and muscles are being brutally torn apart. He screams at first, until the change hits the throat and vocal chords. Normally a human in pain has defenses, such as hormones that dull pain receptors, but those systems are gone too, leaving absolutely nothing to help with the pain. The second season implies that the body breaking down and rebuilding itself makes the werewolf slightly stronger after each transformation.
--->'''Nina:''' It looks so painful. What happens to you, what does it feel like?\\
'''George:''' There aren't words.
** It's implied that when a person dies, they go to an unknown place where terrifying things happen to them. So when a person comes back as a vampire or ghost, they haven't had the best time.
* Zig-zagged with [[OurWerewolvesAreDifferent werewolves]] in ''Series/BuffyTheVampireSlayer''. The pain they go through when transforming [[DependingOnTheWriter varies]]. When Oz transforms from human to werewolf in season 2, the pain is incapacitating: he doubles over, tries to get away but falls over, followed by [[TheStoic restrained]] moaning. Transforming back, however, doesn't even wake him up. In season 3, he's perfectly quiet during ''all'' transformations, while in season 4, the time leading up to nightfall is described as "blood boiling". But [[EvilCounterpart Veruca]] enjoys it. Then in season 8, a group of werewolves is seen screaming and even [[BloodFromTheMouth coughing up blood]], while Bay changes without a hitch. Possibly justified when taking into account how much a werewolf ''wants'' to transform. Oz was quiet when he was safe and behind bars; Veruca loves being a werewolf; and Bay transformed out of protection. Characters who experience pain, however, always seem to fight it.
* ''Series/DoctorWho'':
** The regeneration process experienced by Time Lords, if not always physically painful, is an extremely traumatic and draining experience. Typically, just after regenerating the Doctor is weakened, partially amnesiac, and, in a few cases, comatose.
*** The Master's regeneration in "[[Recap/DoctorWhoS29E11Utopia Utopia]]" shows him screaming throughout the whole process. Extra creepy when his face morphs and the scream pitches up.
*** When the Eleventh Doctor shows up in ''Series/TheSarahJaneAdventures'', Sarah asks him if it hurt the last time he changed. "It always hurts," is his reply.
*** In "[[Recap/DoctorWhoS32E8LetsKillHitler Let's Kill Hitler]]", Mels screams in pain when [[spoiler:she regenerates into River Song.]]
*** In "[[Recap/DoctorWhoS37E1TheWomanWhoFellToEarth The Woman Who Fell to Earth]]", after the Doctor describes regeneration, Grace comments that it sounds painful, to which the Doctor responds that she has ''no'' idea.
** "[[Recap/DoctorWhoS29E8HumanNature Human Nature]]"/"[[Recap/DoctorWhoS29E9TheFamilyOfBlood The Family of Blood]]": When the Doctor becomes (temporarily) human, the process is only seen during a few extremely brief flashbacks — and he's screaming in anguish the entire time.
** The Doctor's forced aging in "[[Recap/DoctorWhoS29E12TheSoundOfDrums The Sound of Drums]]" and again in "[[Recap/DoctorWhoS29E13LastOfTheTimeLords Last of the Time Lords]]" certainly sounds painful, judging by the screaming.
** "[[Recap/DoctorWhoS30E3PlanetOfTheOod Planet of the Ood]]" has the KarmicTransformation of the CorruptCorporateExecutive. It starts as simple hair loss, and ends in him ripping his own face off to expose his newly transformed self and coughing up part of his brain.
* From the Creator/{{Netflix}} show ''Series/HemlockGrove'', Peter Rumancek transforms into his wolf-form twice on the show and each time it's as visceral as it is painful as it looks that the wolf is ''ripping'' it's way out of his body. The first time his eyes and teeth are pushed out of their sockets. The second time ''his wolf head comes out of his human mouth'' and then he touches the guy in front of him with his hand. '''That came out of his muzzle.''' No wonder the guy [[VomitIndiscretionShot pukes his guts]] out at the sight.
* ''Series/{{Heroes}}'':
** When Mohinder injects himself with an experimental serum trying to give himself an ability, his ability at first includes super strength and agility. However, he slowly starts to transform into a monster of sorts and there is visible pain and discomfort that accompanies the transformation.
** Shows up again in season 3 with the VoluntaryShapeshifting ability [[spoiler: acquired by Sylar]].
* ''Series/InFromTheCold'': Jenny's body morphing is very painful, to judge from the cracking and crunching sounds as her skeleton changes, with her voice groaning while in different pitches during all this.
* ''Series/LovecraftCountry'': The transformation potion wearing off is far from pleasant, with the person's original body blooding emerging from their assumed one, which causes a lot of discomfort.
* ''Series/TheOuterLimits1995'':
** In "The New Breed", the substantial modifications made to his body by the nanobots causes Dr. Andy Groenig severe and near constant pain.
** In "[[Recap/TheOuterLimits1995S2E15Afterlife Afterlife]]", Stiles undergoes one in the process of his DNA slowly melding with the aliens'. He first throws up continually, then loses his hair, grows claws on his hands, even his skull and brain enlarges.
* ''Series/{{Supernatural}}'': Shapeshifters have to go through this every time they switch forms, with teeth falling out, internal things rearranging with many a crunching, squelching sound, and finally having to peel their own skin off. Made more jarring and squicky because the first time we see it, the shapeshifter looks like one of the main characters.
* The transformation to vampire in ''Series/TrueBlood'' has been described as incredibly painful and horrifying by vampire protagonist Bill, who had vowed never to turn another human into a vampire to ensure that nobody else has to experience what he went through.
* Werewolves get the really bad end of the stick on ''Series/TheVampireDiaries''; it takes over five hours of horrible pain before there's even any visible changes. Though at least that part does get shorter over time.
* Discussed and subverted in ''Series/WizardsOfWaverlyPlace''; when Justin kisses his werewolf girlfriend and finds out that he's now a werewolf because of it, he freaks out expecting this trope to take effect. Fortunately for him, that's not the case.
-->'''Isabella:''' That's another a stereotype. The change is pretty fast and painless.\\
'''Justin:''' ''[suddenly a werewolf]'' Really?
[[/folder]]

[[folder:Myths & Religion]]
* Some versions of legend about werewolves actually either invert or subvert this trope, saying that while the transformation may appear to be excruciatingly painful, in truth it turns out to be sinfully '''pleasurable''' instead.
[[/folder]]

[[folder:Roleplay]]
* ''Roleplay/RubyQuest'': Ruby [[spoiler:gaining her ThirdEye]] is quite painful. It's explicitly said that "her head is killing her", and her head is bleeding afterwards.
[[/folder]]

[[folder:Video Games]]
* The power-up item Rage Box in ''VideoGame/AmericanMcGeesAlice'' will do this to Alice. If approached, the box sprays a red mist into Alice's face, causing her to scream in agony as she becomes demonic in appearance, with red skin, clawed hands and horns. The resulting transformation increases her striking power immensely.
* In ''VideoGame/BendyAndTheInkMachine'' Chapter 4, some prolonged gurgling audio implies that this happened to [[spoiler:Grant Cohen]]. In [[AllThereInTheManual the game files]], this audio is even labelled [[spoiler:Grant Transformation]].
* Presumably the case for most of the BodyHorror-laden transformations in ''VideoGame/{{Bloodborne}}'', but one explicit case is Vicar Amelia, who goes from a simple holy-looking woman to a humongous, mutated wolf with huge antlers that barely fits inside the cathedral you fight her in, with a GoryDiscretionShot. And [[HellIsThatNoise screaming the entire time, including during the actual battle]].
* In ''VideoGame/{{Cuphead}}'', during [[OurMermaidsAreDifferent Cala Maria]]'s boss fight, she is transformed into a [[GorgeousGorgon gorgon]] by two electric eels, who bite and electrocute her. Judging by her [[OhCrap initial reaction]] and her screams, it was a very unpleasant experience for her.
* In ''VideoGame/DiabloII'', the Dark Wanderer assumes Diablo's true form in the cinematic between Acts 3 and 4, and Marius describes the transformation as "not meant for mortal eyes": Lumps move under his skin, horns sprout from his brow, and his face stretches and twists as he howls in pain. Thankfully, he collapses and the rest of the transformation occurs hidden under his cloak.
* ''VideoGame/DigitalDevilSaga'' has the initial horrific demon transformation. With additional CannibalismSuperpower sprinkles for added taste.
* ''VideoGame/FinalFantasyDimensions'':
** [[spoiler:Vata of the Wind]] renders an intangible enemy vulnerable by allowing it to possess him. In the ensuing boss fight, half his body has been overtaken and transformed into the dark flames that made up the bodies of the Blades of Nil, while his still-normal face is locked in a grimace and he is gripping one transformed arm with his normal one as he begs the party to finish him before his mind is consumed. (It is not likely that they will, and partway through the battle, the rest of his body is overtaken.)
** The final boss has three forms, all of which are [[EvilIsVisceral horrible fleshy mutations]]. The "normal" and "light" forms have a face locked into a ThousandYardStare. The face on the "dark" form is screaming--and it's screaming ''so much'' that it's [[FacialHorror sprouted extra faces beneath its chin]] to scream with.
* ''VideoGame/FireEmblemThreeHouses'':
** Transforming into a Demonic Beast via Crest Stone is demonstrated by [[spoiler:Miklan, who tries wielding the Lance of Ruin without a Crest,]] to be both physically agonizing and terrifying.
** In the Azure Moon Route, the same can also be said of [[spoiler:Edelgard's transformation into Hegemon Edelgard, but she thinks of the pain as nothing compared to the torture she suffered in her past.]]
* In ''VideoGame/{{Folklore}}'', Keats Transcended form basically has him beefing up and changing skin and hair colors. And from the way he screams and writhes around every time you activate it, it's rather unpleasant for him.
* ''VideoGame/InFamous2'':
** Kuo's Conduit powers are activated in this manner. Among other things, Bertrand activated them by draining her blood and replacing it with an unknown liquid.
** There's also Betrand using his powers to convert a man into a Corrupted. While his body slowly mutates, the poor citizen is clearly shown screaming in agony, and when the transformation is complete, he just collapses on the ground, breathing heavily.
* ''VideoGame/JakAndDaxter'':
** Jak being [[InvoluntaryShapeshifter forced]] into his [[SuperpoweredEvilSide dark form]], either by the Oracle or due to an overexposure of [[PsychoSerum Dark Eco]]. The way he jerks and spasms as TheCorruption takes over makes clear it's no picnic. Reverting back, though rather quickly, will have him grabbing his head and shuddering violently. In ''TLF'' it's implied that due to the massive amounts of Dark Eco present, even [[VoluntaryShapeshifting changing voluntarily]] will cause him so much pain that it will kill him.
** Downplayed with Daxter's change from [[RubberForeheadAliens human]] to [[MixAndMatchCritter ottsel]]. "''Man'', that stung!"
* ''VideoGame/Killer7'' features Heaven Smiles as its regular enemies. While some of them are transformed humans, you rarely see the transformations. When you do, they usually feature an instantaneous transformation or an offscreen one. THEN we have [[spoiler: Andrei Ulmeyda]], whose transformation goes like this: [[spoiler: The army, wishing to experiment on him to try and use Smiles as their own weapons, injects potent Heaven Smile tumors into him. The army triggers a small explosion for some reason, but then an even larger explosion occurs and Ulmeyda asks why you didn't kill him at the injection and saying he "can't control this urge to kill." He then screams, his head then flies off his head, his acidic blood (acidic because of all the diseases he infected himself with to create vaccines) kills everyone in the army present, then his blood BRINGS HIS HEAD BACK ONTO HIS BODY AND PULLS UP HIS AFRO. Needless to say, Ulmeyda was in GREAT PAIN in his last moments of sanity.]]
* ''Franchise/TheLegendOfZelda'':
** Whenever Link uses one of his transformation masks in ''[[VideoGame/TheLegendOfZeldaMajorasMask Majora's Mask]]'', it triggers a short cutscene in which he [[https://www.youtube.com/watch?v=cGQas1eAXII screams horribly as the transformation occurs]]. [[http://kotaku.com/why-does-link-cry-in-majoras-mask-its-pretty-dark-1692276196 One Nintendo employee]] provided an explanation that Link's scream may be from ''emotional'' pain rather than physical, saying that Link is being overcome by the sudden and overwhelming feelings of sorrow residing in the mask. These cutscenes can be skipped with the press of a button once you've seen them for the first time.
** ''[[VideoGame/TheLegendOfZeldaTwilightPrincess Twilight Princess]]'', given its tone, has two examples:
*** Link's initial wolf transformation seems to be a dual homage to the transformation scenes in ''Majora's Mask'' and the transformation in ''An American Werewolf in London'', but after that, no further cutscenes of that nature occur.
*** Midna's first transformation with the Fused Shadows has her being thrown around and screaming painfully.
* The original Sega-CD version of ''VideoGame/LunarTheSilverStar'' has [[BigBad Ghaleon]] transform into a [[OneWingedAngel demonic form]] after the heroes initially defeat him. While [[GoryDiscretionShot the camera pans to his feet just before he transforms]], the fact that blood drips on the floor (seemingly from his [[EyeScream eye]] based on the focus there seconds before he transforms and [[spoiler:the fact that the sequel has a resurrected Ghaleon who has a prominent scar over his eye]]) and he's screaming in agony speaks for itself. But once the transformation finishes, his screams seamlessly transition into a [[EvilSoundsDeep deep]] EvilLaugh.
* In ''VideoGame/MegaManZero 4:'' Dr. Weil, when undergoing his final transformation, has tubes being jammed into him (with copious amounts of blood in the Japanese version), and shouting something that roughly translates from Japanese as either "Can you see this Pain?! You'll never understand any of it?!" or "Can you understand pain such as this?!". The drama tapes even include him screaming and grunting in pain as he transforms in such a way that could be considered NightmareFuel.
** Meanwhile, in in the second game, Elpizo gives off an impressive (and horrifying) shriek of pain as he transforms into his OneWingedAngel form.
* The ''VideoGame/ParasiteEve'' series has a handful these transformations to emphasize just how unnatural the game's monsters are; in the first game, the first actual non-boss encounter is a rat which is put through a thoroughly [[https://www.youtube.com/watch?v=FNL8b6Sm3SE traumatic transmutation]]; later on, a poor German Shepherd is given [[https://www.youtube.com/watch?v=YR7hrXqus88 the same treatment.]] Not recommended for the weak of stomach.
* ''VideoGame/Persona5'' has the characters undergo both mental trauma when their Persona first awakens, and then physical as they have to really pull their mask off of them, revealing bloody faces for a bit before transforming. Thankfully, each Phantom Thief just suffers this once.
* ''Franchise/{{Pokemon}}'': If the Pokedex entries in ''VideoGame/PokemonSunAndMoon'' are anything to go by, [[SuperMode Mega Evolutions]] are this to quite a few of the Pokémon if not all of them. The worst part is that unlike other Pokémon evolutions, Mega Evolutions are always reversed once the battle is over, meaning that the very same Pokémon is very likely to undergo the same painful transformation over and over again.
* During [[spoiler:Wheatley's]] transformation in ''VideoGame/Portal2'', [[spoiler:he]] constantly asks [=GLaDOS=] beforehand if it's going to hurt. When she says yes, [[spoiler:he]], knowing [=GLaDOS=], questions whether or not she's just saying that before learning that, for once, she isn't. [[spoiler: It's even more painful for [=GLaDOS=], who can be heard struggling and crying in agony.]]
* The main character in ''[[VideoGame/AlteredBeast Project Altered Beast]]''. The Cut scenes that happen during several of his transformations have such lovely features as his eyeballs bursting, his teeth falling out, his arms exploding to make way for wings and so forth. You can watch them all [[https://www.youtube.com/watch?v=owODa7oelTI here.]]
* In ''VideoGame/QuakeIV'', the player character gets "Stroggified" into one of the enemy zombie-cyborgs, but is rescued before brainwashing and becomes a PhlebotinumRebel. [[https://www.youtube.com/watch?v=CJwyjWpP4XA The Stroggification involves]] getting his legs cut off on a ConveyorBeltODoom. Made all the worse by the player still having some control during the transformation but are unable to free them, as well as having to see (and especially ''hear'') one the fellow Marines undergo the treatment first.
* ''Franchise/ResidentEvil'': The various transformations different characters undergo in the series almost always feature the victims at the most moaning in pain. After being infected with [[PuppeteerParasite Las Plagas]] in ''[[VideoGame/ResidentEvil4 4]]'', both Leon and Ashley experience gruesome chest pains and cough up blood as the parasites slowly take over their bodies, and in ''[[VideoGame/ResidentEvil6 6]]'', the C-Virus infectees actually ''[[ManOnFire burst into flame]]'' before being encased in cocoons.
* In ''VideoGame/TheSecretWorld,'' it's not made explicit in the actual scenario, but lore clarifies that turning into one of the Bee-Imbued is excruciatingly painful -- not that shooting laser beams out of your eyeballs during the initial stage of PowerIncontinence looked ''pleasant.'' Worse: it's implied that pain never goes away, just characters grow accustomed to it and stop paying attention, and that's just the beginning.
-->'''The Buzzing:''' Breathe, sweetling. This too shall pass. Pains are relative, and this one will become very small, in time.
* For the first half of the game ''VideoGame/ShadowHearts'', Yuri Hyuga convulses and screams when using his "Fusion" ability to combine with demons; whether the pain is mental or physical is unknown, but the former is implied. Partway through the game, he experiences an epiphany, whereupon he no longer suffers the FreakOut on using his power. The sequel repeats this pattern, with another epiphany.
* [[spoiler:Naoki's (Main Character), and Chiaki]]'s Transformation in ''VideoGame/ShinMegamiTenseiIIINocturne''.
* ''Franchise/SonicTheHedgehog'':
** The classic games depict the characters screaming when transforming into their [[SuperMode Super forms]], implying that it's a painful process. This is averted in most modern games, however, suggesting that Sonic is used to it by that point.
** Just about every transformation sequence with Sonic turning into the Werehog in ''VideoGame/SonicUnleashed'' looks kinda painful for Sonic. However, transforming back to his normal self is almost instantaneous and looks completely painless, with Sonic looking relieved and content afterward. There's a nice touch in that every time you change the time of day while in the Next-Gen version's [[HubLevel hub worlds]] (either via Pause Menu or with hourglasses) it plays the appropriate transformation sequence as a LoadingScreen. Averted with one cutscene -- near the end, Sonic transforms into his Werehog form, and he barely even flinches. It's implied that he's used to the transformations by now.
** ''[[VideoGame/SonicStorybookSeries Sonic and the Secret Rings]]'': During the FinalBoss, both Sonic and [[BigBad Erazor Djinn]] [[SuperMode go super]] using the World Rings. Judging by the screaming from both of them, as well as the straight-up BodyHorror that Erazor endures on his end, it's not pretty.
* When Rick puts on the Terror Mask for the first time in the ''VideoGame/{{Splatterhouse}}'' remake, it effectively destroys and remakes his muscular structure. He's in agony the entire time, and his flesh ''tears apart'' in the process. In fact, it causes so much damage to him that after ATasteOfPower, the Terror Mask has to turn it down out of risk of killing him.
* In ''VideoGame/TheSurge'', the opening sequence shows the paraplegic PlayerCharacter literally StrappedToAnOperatingTable: The AutoDoc that is meant to be fitting them with their [[SuperWheelchair robotic exoskeleton]] has somehow failed to notice that the anaesthetic failed to take, and [[NoOSHACompliance there's no emergency stop button.]] The results are not pretty. [[FromBadToWorse Nor are they the worst thing to happen the PC that day.]]
* Jelanda's transformation into a monster was offscreen in the original ''VideoGame/ValkyrieProfile''. In the UpdatedRerelease for the PSP, however, it's rendered in CG, and you get to see this innocent (if bratty) teenage girl [[NightmareFuel screaming and crying in pain and fear as her skin mutates into scales]], [[AndIMustScream and her limbs move of their own accord to slaughter the soldiers sent to rescue her while she's utterly helpless to do anything]], until the monstrous flesh finally swallows her face.
* [[http://wow.4fansites.de/bilder/dungeons/thron_des_donners/primordius_04.jpg Primordius]], a boss in ''VideoGame/WorldOfWarcraft'' uses transformations as his main fight mechanic, gaining powerful evolutions as he comes in contact with the mysterious flesh-altering substance that can be found in the boss room. On the other hand, [[https://www.youtube.com/watch?v=dztI4VhawSo&t=60 he makes it perfectly clear that he does not enjoy the process.]]
* [[spoiler:The High Entia's transformation into Telethia]] in ''VideoGame/XenobladeChronicles1''. Particularly notable for Melia, who had to watch one of her own family members do so and even attempt to break free and attack the BigBad's squad. Especially when she then had to ''kill him'' (with his face still visible, even) while on the Bionis Interior.
-->'''LetsPlay/{{Chuggaaconroy}}:''' I don't say this enough, but... ''poor Melia''!
[[/folder]]

[[folder:Western Animation]]
* The ''WesternAnimation/AmericanDad'' episode "Stan Goes on the Pill" has a scene of Stan [[GenderBender transforming into a woman]] as a ShoutOut to ''An American Werewolf in London''.
-->'''Francine:''' Ugh, I have a headache from all this screaming.\\
'''Stan:''' Well, not to compete with you, but I have a headache from my skull changing shape.
* ''WesternAnimation/TheAvengersEarthsMightiestHeroes'':
** The Avengers endure some painful transformations in the episode "Gamma World", as part of The Leader's plan to turn everyone in the world into Gamma-irritated monsters. Iron Man's pain receives particular emphasis, as the animators show the toll the gamma blast takes on his shrapnel-embedded heart.
** Simon Williams' transformation into Wonder Man, in another episode, seems unbearable as well. The other characters mention that Simon became the only person to survive the process.
* ''WesternAnimation/Ben10'':
** Kevin's transformation into his ShapeshifterMashup form ends with him screaming in agony.
** Ben's final stage of transformation into Benwolf. For most of the episode, he'd just been gradually getting furry and wolflike, then... ouch.
* The 2006 revival of ''WesternAnimation/BikerMiceFromMars'' has Stoker change into a rat-like beast called Stoker Rat when under sunlight. The transformation first occurred in the episode "Changes" and happened again in "British Invasion". The transformation is an ode to the transformation scene from ''Film/AnAmericanWerewolfInLondon''.
* ''WesternAnimation/CodenameKidsNextDoor'': During the episode Operation G.R.A.D.U.T.E.S, Father invents a device that turns all the of the members of the Kids Next Door into animals and the transformations are not pretty. Numbuh 5, who was turned into a gazelle, was screaming in pain until the point she no longer could and the rest of Sector V was also shown to be in a large amount of pain.
* ''WesternAnimation/DannyPhantom'' actually has ''five'' instances, all Danny. The first and last sets of two are all seen as excruciating agony. The middle one is NightmareFuel and what follows is just as disturbing and ''really'' should have earned a higher rating.
* ''WesternAnimation/DextersLaboratory'' has Dexter transform into a clown whenever he laughs because another clown's dentures flew off and bit him on his [[{{Pun}} funny bone]] at Dee Dee's birthday party. It's undone at the end when Dee Dee takes up miming lessons to subdue his clowning around and causing destruction throughout the city, then taking him back to the lab to administer an antidote.
* ''WesternAnimation/GarfieldHis9Lives'', [[https://www.youtube.com/watch?v=Y6vdg2ytDy0 life 7]] (about 3 minutes in, and be grateful [[ShadowDiscretionShot the final takes aren't shown]]).
* ''WesternAnimation/{{Gargoyles}}'':
** Derek has a particularly painful one when he turns into a mutate.
** Demona is eventually given the ability to become human by day instead of stone. The change is agonizing ''both'' ways. It was actually painless the first time, though, as Puck, who gave her this ability, [[WordOfGod wanted to surprise her]]. When Macbeth (to whom she's magically connected) is nearby, he feels the transformation too.
* PlayedForLaughs in the first episode of ''WesternAnimation/InvaderZim''. As a machine gives Zim his human disguise (offscreen), he screams "Why does it ''hurt?!''" (For the record, his disguise is [[PaperThinDisguise a wig and a pair of contacts]].)
* ''WesternAnimation/TheMask'' animated series also has some of it, but mostly while Stanley is removing the mask. Which is only sensible, since pulling the mask off basically requires him to ''tear off his face''.
* Parodied in ''WesternAnimation/SouthPark'' Season 14 Episode 9 [[Recap/SouthParkS14E9ItsAJerseyThing It's a Jersey Thing]], when Kyle "transforms" into his Jersey self, "Kyley-B" when South Park is being invaded by New Jersey folk.
* ''WesternAnimation/SpiderManTheAnimatedSeries'': Spider-Man himself undergoes this during the "Neogenic Nightmare" arc. It starts with simple bouts of PowerIncontinence, and is then followed with debilitating pain in his sides, which he describes as feeling like "getting a massage from [[WolverineClaws Wolverine]] -- from the inside." Finally, he sprouts [[MultiArmedAndDangerous four extra arms]] before painfully transforming into a monstrous half-man/half-spider creature. An alternate Man-Spider shows up in one of the later episodes when Spider-Man has to team up with his alternates. That Peter accepted the mutation fairly well, but the villain forced him to be Man-Spider at the worst time. Man-Spider's later fate is unknown but presumably he's back to normal.
* ''WesternAnimation/SpongeBobSquarePants'':
** In "I Was a Teenage Gary", [=SpongeBob=] is accidentally injected with snail plasma by Squidward to cure his pet snail, Gary. Squidward assures [=SpongeBob=] that he'll be fine, and he believes him. But the next day, he starts exhibiting snail-like behavior, including meowing, eating snail food, and walking slowly. His fears are turned into reality as he goes through the gradual transformation into a snail.
** In the episode "Mermaid Man and Barnacle Boy IV", [=SpongeBob=] accidentally puts DesignatedVictim Squidward through a series of increasingly painful and graphic transformations (burning, being cut in half, being skinless, and some that were so grotesque they were only heard offscreen as sound effects that don't bear thinking about) while trying to undo the effects of a "[[IncredibleShrinkingMan small ray]]".
** "The Inside Job" has Plankton going inside [=SpongeBob=]'s body and attaches a sucking helmet to his heart to gain information about the Krabby Patty formula. This ends up causing him to turn into a small version of [=SpongeBob=], with a sequence complete with eyelashes breaking through his skin and his teeth shattering to make way for two goofy buck teeth. Then, at the end, Sponge!Plankton gets attached to Patrick and we get a similar sequence where he becomes a dumb pink plankton.
* In ''WesternAnimation/StreetSharks'', getting turned into a mutant always involves a good bit of screaming. Makes sense, considering that occasional extra limbs are grown and all of them gain a good amount of extra muscle mass.
* ''WesternAnimation/StevenUniverseFuture'': While at the beginning he just glows pink, in the second half of the epilogue, Steven's body starts to randomly swell up whenever he is in a great emotional distress, because of his untreated trauma and PTSD caused from [[CerebusRetcon everything he experienced in the original series]]. It reaches a breaking point in "Everything's Fine", where he has a spectacular mental breakdown, which the episode ends with pink spikes violently bursting out of his back, starting his corruption into a Kaiju-like rampaging monster.
* ''WesternAnimation/TeenTitans2003'':
** Most of Beast Boy's transformations appear painless, except for the episode when an accidental shower of chemicals caused him to morph into a [[ComicBook/TheIncredibleHulk Hulk]]-like werebeast against his will.
** Also, Red Star, from the episode "Snowblind", definitely has this problem.
* ''Franchise/TeenageMutantNinjaTurtles'':
** Donatello's secondary mutation from the "Good Genes" arc of ''WesternAnimation/TeenageMutantNinjaTurtles2003''. The transformation itself -- which happens after a long illness -- is fairly brief, but still enough to leave him screaming in pain.
** In the [[WesternAnimation/TeenageMutantNinjaTurtles2012 2012 cartoon]], apparently, getting doused in Mutagen and undergoing a mutation is agonizing if you were human. When Mutagen Man is created, he screams that it burns.
* ''Franchise/{{Transformers}}'':
** If one of the eponymous Transformers hasn't transformed in an exceedingly long time, or is banged up badly enough, transforming can hurt like hell, or, in extreme cases, be fatal.
** When [[spoiler:Waspinator]] is put into Blackarachnia's transwarp machine in ''WesternAnimation/TransformersAnimated'', he screams and his hands can be seen clawing at the machine. Blackarachnia casually comments that it might hurt a bit.
** Most upgrades the Transformers experience in ''WesternAnimation/BeastWars'' seem to come off this way. Everyone's transition to Transmetal in the season 2 premier was accompanied by screams and bodies collapsing. The changes to Transmetal 2 seemed even worse.
** ''WesternAnimation/TheTransformers'': In "The Burden Hardest to Bear", Scourge takes on the Matrix of Leadership, which makes him extremely powerful, but warps his body, which looks extremely painful and even makes him cry.
* Matt from ''WesternAnimation/{{WITCH}}'' always has to brace himself before turning into Shagon.
[[/folder]]

* ''Literature/TheVampireChronicles'' transformation includes the body painfully rejecting digested food and fluids.
* ''Literature/PercyJacksonAndTheOlympians'': While the scene following Percy's transformation into a Guinea pig is oddly funny, the way he describes the actual process hardly sounds fun. Like [[Film/OzTheGreatAndPowerful an above example]], he's tricked into drinking a potion and says it felt like sudden, burning heat in his stomach, unnatural physical changes, and then terror, because he had no idea what was happening.
* ''Literature/{{Twilight}}'' vampire transformations are described as three straight days of burning, terrible pain. But you can choose not to scream if you really don't want to.
* OlderThanPrint: In Myth/IrishMythology, "The Boyhood Deeds of Cuchulainn" from the ''Literature/TheCattleRaidOfCooley'' describes Cuchulainn's Riastarthae (warp-spasm) as a very painful-sounding transformation.
* ''Literature/TheStrangeCaseOfDrJekyllAndMrHyde'': When Dr. Jekyll drank his potion, "the most racking pangs succeeded: a grinding in the bones, deadly nausea, and a horror of the spirit that cannot be exceeded at the hour of birth or death."
* Inferno XXIV of ''Literature/TheDivineComedy'' gives a vivid account of thievish shades transforming into snakes and lizards, and vice versa. The transformation is treated like a rape, a topic so horrid Dante only explicitly mentions it in the context of Lucifer's rebellion against Heaven.

* ''Literature/DrFranklinsIsland'' by Ann Halam, two girls get turned into a fish and a bird. The narrator describes this as being really uncomfortable. The bird-girl's sternum goes clean through the skin of her chest, [[BodyHorror not a pretty picture]]. The transformation back is much easier on both of them, but the fish-girl is sick and uneasy for much of it and the bird-girl spends five days in something like a coma.
* In ''Literature/GauntsGhosts'', the [[spoiler:rogue]] Inquisitor Handro Rime has a collection of agents known collectively as the Sirkle. They all share the same face, to act as doubles for the Inquisitor, and it is [[spoiler: implied the two scenes that he dies in are in fact his doubles]]. It's revealed that they use a special form of internal mechanism to alter the tension and position of muscles and even ''fracture and reset bone''. It is repeatedly noted that it is incredibly painful, requires immense focus to maintain one face, and a moment of surprise causes them to reveal their true face. And whenever they transform, it occurs with a [[NauseaFuel horrifying crunch of bone]]. [[spoiler:Cue HeroKiller moments.]]
* Werewolves in ''Literature/TheParasolProtectorate'' face this problem when shifting between human and wolf forms. The physical pain never lessens, but older wolves get better at hiding it, culminating in [[BadassBookworm Professor Lyall]] who is the most graceful shifter anyone in the cast has ever seen. The initial metamorphosis is also generally painful, but only because it normally involves [[ThisIsGonnaSuck an Alpha werewolf tearing you a new one]].
* Roger's [[HenshinHero transformation]] in ''Behemoth'' is accompanied by BloodFromEveryOrifice, which coagulates and becomes InstantArmor and generally happens in response to grievous bodily harm. Comes with dangerous hypotension afterward.
* In ''The Shattered World'', were-folk transformations become more and more painful the older they get.

* ''Literature/JourneyToChaos'':
** The transformation caused by mana mutation is always painful because it reshapes the victim's body at random. All the while the brain is receiving signals of what's happening, including ones that it doesn't know how to interpret.
** ''Literature/LoomingShadow'' has many examples of how painful this can be. Patrick Lumberson lay halfway between human and fitzger with {{mana}} sparking on him like electricity. Kallen encounters a monster in the midst of transforming and mistakes its screams of pain for threatening hisses. [[spoiler: The reader sees into Eric's mind when it is shorting out from a mana explosion.]]
** Bladi Conversion is a [[TheDarkArts a Forbidden Technique]], in part, ''because'' it is painful. The convertor replaces the genetic information in the converted's blood by overwriting it, in effect, replacing the converted's parents, biologically speaking. [[spoiler: Zettai]] describes it as ''the'' most painful thing she's ever experienced.
* All werewolves in ''Literature/DarkestPowers'' first transform during puberty. Derek's was shown to be extremely painful.
* Paelen from Kate O'Hearn's ''Pegasus'' series can stretch his bones almost indefinitely. While this is a useful skill in a series where the protagonists keep getting captured, it also hurts like crazy.
* In Tansy Rayner Roberts's ''Creature Court'' series, the characters can usually shift into animal, Lord or chimaera form pretty easily. However, if they've had recent contact with [[KryptoniteFactor skysilver]], the transformation becomes a ''lot'' more unpleasant. Naturally, this happens to Ashiol at every given opportunity.
* ''Literature/MonsterHunterInternational'': Werewolf transformations always hurt since the body's very skeletal structure is transforming, much less the other body changes, though the pain get easier to handle (or at least acclimate to) with experience. Also played with, in that according to Earl Harbinger [[spoiler:speaking from experience]], pain itself can often be a catalyst for InvoluntaryShapeshifting as a werewolf can instinctively try to go beast when hurt (usually to try and better murder whatever caused it), and it takes training to ''only'' transform on command (at least until the full moon comes out).
* In ''Literature/RiversOfLondon'', the disguise-spell ''dissimulo'' molds flesh and bone into a new appearance, and subverts this trope by dulling the resulting pain ... at least, until the spell shuts down. Then, the pain of having ''most of your face collapse'' is the least of your problems.

* ''Webcomic/ElGoonishShive'':
** This is a problem for [[HalfHumanHybrid chimera]]; it figures prominently in the character of [[http://www.egscomics.com/?date=2004-04-07 Vlad]], who could not change form with risking his life. Part of what makes Grace (Shade Tail) unique is that transforming doesn't hurt her as much as it does others (by design, she naturally releases painkillers when transforming). Vlad is eventually put into a human form via TFG (or the equivalent thereof), thereafter ''refusing'' to try transforming again, both out of fear of this trope and that [[GenderBender she]] will be unable to turn back since it wasn't possible on her own.
** Interestingly, the transformation gun doesn't have this effect, even on normal humans (though it is implied that it did before Tedd perfected it; when Elliot uses the transformation belt, which is based on an earlier version of the TFG, he is incapacitated for several minutes -- and his later cat-hybrid transformations reflect this as well [[spoiler:[[https://www.egscomics.com/comic/party-264 until they don't]]]]). "OK, I need an aspirin, a ball of yarn, and thirty-seven pounds of catnip, stat!"

%%--> ''"Wait, painful? This is going to hurt?"''
%%--> ''"In ways you have never imagined..."''
%%--> ''"meep."''

* Mina from ''Webcomic/UncommonAnimals'' is not happy about [[http://uncommonanimals.thecomicseries.com/comics/31 changing.]]
* K.A.'s upgrade in ''Webcomic/WeAreTheWyrecats'' is visibly painful for her.

* ''Wiki/SCPFoundation'', [[http://www.scp-wiki.net/scp-1575 SCP-1575 ("Venus Statue")]]. When an animal drinks water that has passed through SCP-1575, it mutates into a human being. If it survives the process, the former animal describes it as being extremely painful. The water doesn't lose its potency after ingestion either; the SCP has to check animals for internal and external parasites after there was a half-mutated flea and a human-faced tapeworm screaming as it burst out of a dog's belly.

* ''WebVideo/TheVelociPastor'', in which a kind pastor transforms into a dinosaur, hands first, while writhing in pain and staring at himself in horror in his apartment mirror.
%%* Spoony to Dr. Insano in ''WebVideo/{{Kickassia}}'' on Website/ThatGuyWithTheGlasses.

* The 2006 revival of ''WesternAnimation/BikerMiceFromMars'' has Stoker change into a rat-like beast called Stoker Rat when under sunlight. The transformation first occurred in the episode "Changes" and happened again in "British Invasion". The transformation is an ode to the transformation scene from ''Film/AnAmericanWerewolfInLondon''.
* If one of the eponymous Franchise/{{Transformers}} hasn't transformed in an exceedingly long time, or is banged up badly enough, transforming can hurt like hell, or, in extreme cases, be fatal.

* PlayedForLaughs in the first episode of ''WesternAnimation/InvaderZim''. As a machine gives Zim his human disguise (offscreen), he screams "Why does it ''hurt?!''" (For the record, his disguise is [[PaperThinDisguise a wig and a pair of contacts]].)
* ''WesternAnimation/SpongeBobSquarePants'':
** In "I Was a Teenage Gary", [=SpongeBob=] is accidentally injected with snail plasma by Squidward to cure his pet snail, Gary. Squidward assures [=SpongeBob=] that he'll be fine, and he believes him. But the next day, he starts exhibiting snail-like behavior, including meowing, eating snail food, and walking slowly. His fears are turned into reality as he goes through the gradual transformation into a snail.
** In the episode "Mermaid Man and Barnacle Boy IV", [=SpongeBob=] accidentally puts DesignatedVictim Squidward through a series of increasingly painful and graphic transformations (burning, being cut in half, being skinless, and some that were so grotesque they were only heard offscreen as sound effects that don't bear thinking about) while trying to undo the effects of a "[[IncredibleShrinkingMan small ray]]".
** "The Inside Job" has Plankton going inside [=SpongeBob=]'s body and attaches a sucking helmet to his heart to gain information about the Krabby Patty formula. This ends up causing him to turn into a small version of [=SpongeBob=], with a sequence complete with eyelashes breaking through his skin and his teeth shattering to make way for two goofy buck teeth. Then, at the end, Sponge!Plankton gets attached to Patrick and we get a similar sequence where he becomes a dumb pink plankton.
* ''WesternAnimation/GarfieldHis9Lives'', [[https://www.youtube.com/watch?v=Y6vdg2ytDy0 life 7]] (about 3 minutes in, and be grateful [[ShadowDiscretionShot the final takes aren't shown]]).
* ''WesternAnimation/DannyPhantom'' actually has ''five'' instances, all Danny. The first and last sets of two are all seen as excrutiating agony. The middle one is NightmareFuel and what follows is just as disturbing and ''really'' should have earned a higher rating.
* ''WesternAnimation/Ben10'':
** Kevin's transformation into his ShapeshifterMashup form ends with him screaming in agony.
** Ben's final stage of transformation into Benwolf. For most of the episode, he'd just been gradually getting furry and wolflike, then... ouch.
* Parodied in ''WesternAnimation/SouthPark'' Season 14 Episode 9 [[Recap/SouthParkS14E9ItsAJerseyThing It's a Jersey Thing]], when Kyle "transforms" into his Jersey self, "Kyley-B" when South Park is being invaded by New Jersey folk.
* In ''WesternAnimation/StreetSharks'', getting turned into a mutant always involves a good bit of screaming. Makes sense, considering that occasional extra limbs are grown and all of them gain a good amount of extra muscle mass.
* ''WesternAnimation/TheAvengersEarthsMightiestHeroes'':
** The Avengers endure some painful transformations in the episode "Gamma World", as part of The Leader's plan to turn everyone in the world into Gamma-irritated monsters. Iron Man's pain receives particular emphasis, as the animators show the toll the gamma blast takes on his shrapnel-embedded heart.
** Simon Williams' transformation into Wonder Man, in another episode, seems unbearable as well. The other characters mention that Simon became the only person to survive the process.
* ''WesternAnimation/{{Gargoyles}}'':
** Derek has a particularly painful one when he turns into a mutate.
** Demona is eventually given the ability to become human by day instead of stone. The change is agonizing ''both'' ways. It was actually painless the first time, though, as Puck, who gave her this ability, [[WordOfGod wanted to surprise her]]. When Macbeth (to whom she's magically connected) is nearby, he feels the transformation too.

* ''Franchise/TeenageMutantNinjaTurtles'':
** Donatello's secondary mutation from the "Good Genes" arc of ''WesternAnimation/TeenageMutantNinjaTurtles2003''. The transformation itself -- which happens after a long illness -- is fairly brief, but still enough to leave him screaming in pain.
** In the [[WesternAnimation/TeenageMutantNinjaTurtles2012 2012 cartoon]], apparently, getting doused in Mutagen and undergoing a mutation is agonizing if you were human. When Mutagen Man is created, he screams that it burns.
* ''WesternAnimation/SpiderManTheAnimatedSeries'': Spider-Man himself undergoes this during the "Neogenic Nightmare" arc. It starts with simple bouts of PowerIncontinence, and is then followed with debilitating pain in his sides, which he describes as feeling like "getting a massage from [[WolverineClaws Wolverine]] -- from the inside." Finally, he sprouts [[MultiArmedAndDangerous four extra arms]] before painfully transforming into a monstrous half-man/half-spider creature. An alternate Man-Spider shows up in one of the later episodes when Spider-Man has to team up with his alternates. That Peter accepted the mutation fairly well, but the villain forced him to be Man-Spider at the worst time. Man-Spider's later fate is unknown but presumably he's back to normal.
* ''WesternAnimation/StevenUniverseFuture'': While at the beginning he just glows pink, in the second half of the epilogue, Steven's body starts to randomly swell up whenever he is in a great emotional distress, because of his untreated trauma and PTSD caused from [[CerebusRetcon everything he experienced in the original series]]. It reaches a breaking point in "Everything's Fine", where he has a spectacular mental breakdown, which the episode ends with pink spikes violently bursting out of his back, starting his corruption into a Kaiju-like rampaging monster.
* The ''WesternAnimation/AmericanDad'' episode "Stan Goes on the Pill" has a scene of Stan [[GenderBender transforming into a woman]] as a ShoutOut to ''An American Werewolf in London''.
-->'''Francine:''' Ugh, I have a headache from all this screaming.\\
'''Stan:''' Well, not to compete with you, but I have a headache from my skull changing shape.
* ''WesternAnimation/CodenameKidsNextDoor'': During the episode, Operation G.R.A.D.U.T.E.S, Father invents a device that turns all the of the members of the Kids Next Door into animals and the transformations are not pretty. Numbuh 5, who was turned into a gazelle, was screaming in pain until the point she no longer could and the rest of Sector V was also shown to be in a large amount of pain.

%% Image selected per Image Pickin' thread: https://tvtropes.org/pmwiki/posts.php?discussion=1510294360078295300
%% Please do not replace or remove without starting a new thread.

* When the title character of ''Manga/{{Naruto}}'' releases his Demon Fox power at the [[FourIsDeath four tails]] level, his skin peels off before burning into ash, and blood covers his entire body to form the Kyuubi's body. Also, he loses consciousness because of the injuries to his body, and the Demon Fox takes control of it. Changing back is also incredibly painful as he temporarily ''has no skin''. Even the lesser forms are painful to an extent. The chakra is poisonous to Naruto and constantly burns his skin, only the accelerated healing it grants preventing him from succumbing to the damage.
* [[DarkMagicalGirl Princess Kraehe]] of ''Anime/PrincessTutu'' goes through a painful, involuntary transformation to unlock her SuperpoweredEvilSide.
* Tiara and Leon's transformations in ''Anime/ShamanicPrincess''. At least those work like they're supposed to -- it gets worse when [[spoiler:her best friend]] forces the transformation.
* ''Anime/DigimonFrontier'': The Beast Spirit Evolutions have a painful yell as the characters evolve. Kouji in particular will sometimes suffer pain and/or weakness after ''de''-transforming, whether the transformation was painful or not, leading to {{Fanwank}} about what just what it is that makes it so hard on Kouji alone. Adding to this, Kouji and Kouichi most likely go through the most painful transformations of them all. This may be because the Beast Spirits bend their bones, flesh, and bodies to match their evolution. Everyone else is rather human-shaped while these two have to suffer a complete bone re-structure.
* Although not quite as much, the evolution sequences in ''Anime/DigimonTamers'' show the Digimon in slight pain as their skin is peeled off.
* ''Franchise/LyricalNanoha'':
** Vivio's forced transformation [[spoiler:into her [[OvernightAgeUp Sankt Kaiser form]]]] in ''Anime/MagicalGirlLyricalNanohaStrikers'' involved a lot of convulsing and screaming in pain.
** Hayate's similar transformation at the end of ''Anime/MagicalGirlLyricalNanohaAs'' appears similarly painful, but as her body is at this point being controlled by an A.I., it seems unlikely that she felt it.
* Various instances in ''Anime/EtoRangers'':
** While it's not explored much in the show, Hols's SuperMode, changing from an anthropomorphic bull into a much stronger feral one, is implied to cause him a lot of pain and distress in his ImageSong. Understandable, considering that his TransformationTrinket -- [[BullSeeingRed the color red]] -- is, as he points out in the song, [[BlessedWithSuck completely unavoidable]].
** When [[BrainwashedAndCrazy under Jyuken the Gatekeeper's control]], Pochiro, Pakaracchi, and Tart ''begin'' to come to their senses, only for Jyuken to stop it in its tracks by forcing the former two into hulking monstrosities. Tart [[SubvertedTrope successfully fights the transformation process]], but judging from her cringing and inability to move, it certainly wasn't an easy fight, and she almost lost.
** [[spoiler:Chocolat's transformation into Nyanma]]. Evil energy pulses around her, her eyes dilate, her muscles tighten, and she screams in agony the whole time.
* Valgaav from ''LightNovel/{{Slayers}} TRY'' is capable of a partial transformation into his dragon form. The transformation appears so painful to him that he never manages to transform fully.
* In ''Anime/{{S cry ed}}'', Kazuma and eventually [[spoiler:Ryuho, Martin Zigmarl and Straight Cougar]] damage their bodies when they go into their alter forms. Usually, the scars appear where the armor does. For example Kazuma gets scars on his arm, then on his face and even part of his hair starts to change. By the end of the series, he doesn't even open his right eye unless he's in his alter form (which he might possibly not even ''have'' outside of his alter form). They look pretty scary during the last fight.
* ''Manga/DNAngel'':
** Hiwatari's transformation into Krad is very painful, one of the factors being the fact that he usually fights it quite hard. Contrast with Daisuke's relatively easy transformation in to Dark, only experiencing pain for the first time and [[spoiler:when he grows his own wings in the final episodes.]]
** In the manga, Daisuke feels pain when transforming [[spoiler:after Risa was kidnapped off the Farris Wheel because he transformed with anger, not love.]] This could also explain why transforming is so painful for Satoshi. [[spoiler:The one time he did transform with little-to-no pain was after diving to save Risa when she fell off the tower, transforming out of "love" (according to some fans).]]
* Tsubasa's first transformation into ''Anime/Figure17TsubasaAndHikaru'' seems to cause her pain for unknown reasons, although as she's presented floating in some kind of CyberSpace environment, it might be purely mental.
* Mamoru Kusanagi from ''Manga/BlueSeed'' bleeds green blood when he brings out his arm blades.
* While it is inconsistently portrayed (at least in the manga), the more extreme renditions of Chise's transformations into [[PersonofMassDestruction the Ultimate Weapon]] in ''Manga/{{Saikano}}'' are agonizingly painful for her.
* The title haibane of ''Anime/HaibaneRenmei'' are born looking like normal humans, until their wings grow during their first night in the town. Having a pair of wings explode out from one's shoulder blades is about as painful as it sounds.
* A lot of this in ''VideoGame/ArcTheLad'', [[spoiler: as for chimera transformations]]. ''A lot.''

* ''Anime/DragonBallZ'':
** Freeza's transformations in particular tended to involve a lot of screaming and incredibly painful-looking contortions.
** Buu's de-transformation from Super Buu to Kid Buu consisted of nothing ''but'' standing around and screaming for a very long time, but that may have been less physical pain and more that he was devolving from a fairly intelligent AxCrazy to a mindless OmnicidalManiac.
** Ditto for Goku's first-time Super Saiyan 1 and 3 transformations. Goku's transformation into [=SSJ3=] however is more exhausting than painful though.
** The Legendary Super Saiyan's first transformation of Broly (in [[Anime/DragonBallZBrolyTheLegendarySuperSaiyan his first movie]]) and Kale (in ''Anime/DragonBallSuper'') seems to be extremely painful.
*** For Broly (DBS), the Wrath State causes him a great deal of physical pain due to his power erupting and his body expanding in muscle mass. He can be seen clutching his head in pain, and though it seems like it, the constant screaming is not entirely because he's angry, but due to the constant pain he's in. It only gets worse when Broly turns Super Saiyan, where he loses all trace of sanity.
* ''Anime/EurekaSeven'': Eureka's wings growing from her back is not a pleasant experience.

* In ''Manga/NegimaMagisterNegiMagi'', the chronic [[ImHavingSoulPains soul pains]] that Negi suffers ever since learning [[DangerousForbiddenTechnique Magia Erebea]] are a symptom of him being [[spoiler:''turned into a demon'' by overuse of the technique]].
* Even though Ichika's later transformations in ''Anime/UtaKata'' are perhaps not physically painful as such (although she tends to become nauseous), they are ''extremely'' unwanted and emotionally scarring.
* Evangelion Unit 02's [[BerserkMode Beast Mode]] in ''Anime/RebuildOfEvangelion 2.0'' requires of a painful realignment of the spine held in place by 10 pylons, all fed back to the pilot via [[EmpathicWeapon Empathic Link]]. [[spoiler:Mari]] was very visibly affected by this.
* Transforming into a Hollow in ''Manga/{{Bleach}}'' seems to be an agonizing process, if the Pluses' reactions to it are to go by.
* Not sure if it counts as a transformation, but in ''Anime/HellGirl'' season 3, Yuzuki after [[spoiler:being possessed by Ai]] goes through a surreal sequence where she convulses and screams as this egg-thing comes out of her back. The poor girl has to go through this every time [[spoiler:Ai is contracted to send someone to Hell]].
* In ''Anime/MahouNoMakoChan'', [[https://www.youtube.com/watch?v=drOHCAlII0Q&feature=player_embedded#at=132 Mako's transformation]] from mermaid to human is pretty disturbing, complete with DerangedAnimation, Mako screaming, and the ocean and moon turning red.
* In ''Manga/FullmetalAlchemist'', [[spoiler:Ling's transformation into Greed and Bradley's transformation into Wrath]] both have the transformees look like they're being ''torn apart'' and [[spoiler:Bradley]] describes it as a continuous cycle of dying and being revived until he pulls through.
* Late in ''Manga/InuYasha'', the title character is forced to use a [[MineralMacGuffin Jewel Shard]] on the Tetsusaiga to give him a power boost; however, the jewel becomes corrupted and forces him to transform into a [[AxeCrazy full]] [[SuperPoweredEvilSide demon]]. Given how much he is screaming, it's safe to assume the forced transformation is pretty damn painful.
* In ''Anime/YuGiOhGX'', [[spoiler:Yubel was [[WasOnceAMan originally a young child]] and a friend of a prince who would become Judai in a later life. He ([[AmbiguousGender or maybe she, it's hard to tell)]] volunteered to become Judai's spiritual guardian, and became the demonic Duel Spirit that was first seen in the third season. The process -- which seemed to combine alchemy with surgery -- was only seen briefly, but given what we did see -- and hear -- it likely was ''very'' painful for Yubel.]]
* ''Anime/YuGiOhArcV'': Whenever any of the four boys Awaken, they are often mentally in pain, their bodies heat up and their chests tighten up.
* Jarbilong in ''Manhwa/{{Priest}}'' uses the body of a former vicar to take physical form in his battle against Ivan Isaacs. The poor sod screams ''a lot'' while his ribs stretch out of his chest and a new head grows out of his back.
* In ''Anime/ErgoProxy'', Ergo Proxy's first couple of on-screen transformations involve lots of painful screaming. The transition seems to become smoother later on.
* When Akatsuki from ''Anime/LogHorizon'' uses the shapeshifting potion to edit her character the transformation is accompanied by bursts of light, sickening cracking sounds and a lot of screaming.
* A slightly different version in ''Anime/HowlsMovingCastle'' - Howl can turn into a giant bird-thing pretty easily. It's changing ''back'' that hurts.

* In ''ComicBook/WerewolfByNight Volume 1'', [[PunnyName Jack Russell]]'s transformation into a werewolf gets more painful each time he goes through it, escalating to levels of unbearable agony by the time he's been one for less than two years. And it's not just physical, either: every time he changes it feels as if [[ImHavingSoulPains his soul is being torn apart]]. After [[spoiler:he gains control of the change]] it becomes less painful to shift, but one is left to wonder [[FridgeHorror what would have happened if he never had]]...

* After acquiring a book that governs the rules of magic in ''ComicBook/BuffyTheVampireSlayer Season 10'', Dracula has Xander write into it that "Dracula became the most powerful vampire of all". All right, Dracula, one incredibly agonizing transformation into [[spoiler:the massive demon responsible for creating vampires in the first place]], coming right up.
* ''ComicBook/WonderWoman'': The way people react when [[ReforgedIntoAMinion being turned into]] Circe's [[BalefulPolymorph Beastiamorphs]] indicates that it is a very painful and horrific experience.
** ''ComicBook/WonderWoman1942'': Maj. Keith Griggs collapse and screaming transformation when Circe nabs him is a good example of just how unpleasant being transformed into one of Circe's loyal mooks can be.

* In Disney's ''WesternAnimation/{{The Little Mermaid|1989}}'', Ariel's tail is literally torn in half as she is changed into a human. The facts that it occurs in silhouette and the two ragged halves become shapely legs almost instantly does little to ease the horror of the scene. And of course, [[{{Disneyfication}} Disney being what it is]], this is actually ''toned down'' from the [[Literature/TheLittleMermaid original fairy tale]]. Not only was the transformation excruciating, but afterwards she felt like she was walking on knives the entire time she was transformed.
* ''WesternAnimation/SnowWhiteAndTheSevenDwarfs'': As the Evil Queen becomes an [[VainSorceress ugly witch]], she clutches her throat, seemingly in pain, while wearing an expression of raw horror. She gets over that quickly, though.

* In the climax of ''WesternAnimation/AtlantisTheLostEmpire'', Milo slashes the villain, [[spoiler:Rourke]], across the arm with a piece of the magic Atlantean crystal, leaving a spot of pure crystal on his arm...which [[BalefulPolymorph instantly starts spreading]] across his entire body. BodyToJewel has never looked so painful.

* Bavmorda's "You're all pigs!" spell in ''Film/{{Willow}}'' cannot be described as pleasant. Every victim screams in pain and wriggles on the ground as they transform.

* The first transformation sequence in ''Film/TheCompanyOfWolves'', wherein a werewolf, having disappeared for several years, flies into a rage over being forgotten by his lover. He begins to tear his own face off before his flesh splits open by itself, revealing the intricate details of the human anatomy for a few moments before the muscles and bones begin to twist into the shape of a wolf's, the visceral display traumatizing the woman's children all the while. Then his former lover's husband returns to the house and beheads him. His head goes flying into a vat of milk, then resurfaces as a human head, his blood staining the milk pink. Delicious!
** A later transformation sequence is taken from folklore: A jilted witch curses her ex-lover's entire wedding party to become wolves until she changes them back. Considering that the wolf-forms erupt through the victims' mouths, and the sheer volume of screaming involved -- yeah, not pleasant.
* In ''Film/DogSoldiers'', the transformation into a werewolf is apparently very painful, as the unfortunate lycanthrope-to-come begins screaming and grunting as they stagger around the room, tripping over random objects, as fur begins to grow and they generally display more wolf-like characteristics as the change continues, growling instead of crying for example.
* In Makodap's short film ''11'', the main character Peter Baxter attempts to flee from a luxury resort without paying his bill. He is tricked by the company and is painfully transformed into an attractive young woman. The [[https://www.youtube.com/watch?v=606fx-y6puQ painfulness of the transformation]] is intense with Peter screaming in agony, as bones break and reform. The company intends to get their money somehow, and have plans for Peter, or Nikki as he will be known as.
* ''Film/GhostRider2007'': Johnny Blaze's first transformation into the Ghost Rider has his skin burning and melting off. He goes beyond the point of screaming in pain and winds up laughing maniacally before the process finishes. Subsequent transformations are instantaneous and seemingly painless -- unless the Ghost Rider just doesn't acknowledge pain.
* Sebastian becoming invisible in ''Film/HollowMan'', as well as making the previous test subject visible again.
* Ron Howard wanted something like this originally for the bathtub scene in ''Film/{{Splash}}'' where Madison the mermaid turns into her mermaid form in the bath, but he feared that it would ruin the appeal of the character. The part where her lower torso bubbles and turns scaly is a bit eerie, but Madison seems pretty relaxed about it.
* ''Film/TheMask'': The first time Stanley puts on the mask. All the times it occurs later it's off-screen, for a good reason. Though thankfully it’s a lot less painful coming off and even better The Mask is a genuinely insane but a sweet, kind hearted polite person who other than shoving exhaust pipes into the bottoms of the mechanics is pretty much harmless and wants fun most of the time. The Mask Pressbook has this to an extreme in their test images of Jim Carrey turning into the Mask. One of them looks like it was borrowed from ''The Howling'' or ''American Werewolf in London''. There are pictures of that on [[http://www.jimcarreyonline.com/forum/viewtopic.php?t=8492 Jim Carrey Online.]]
* In ''Film/{{Innerspace}}'', Tuck uses a procedure on Jack to reshape his facial features to disguise him. He warns him beforehand that it will hurt, and it certainly does. (And hurts even worse when it wears off prematurely and his face snaps back to normal.)
* The poor title character of the dark and edgy ''Film/KamenRider'' {{deconstruction}} film ''Film/ShinKamenRiderPrologue'' suffers from this. Rather than simply having the "armor" appear over his body, Shin's body actually changes, distorts and morphs into the Shin Kamen Rider. This is only done twice in the film and is extremely painful for the guy (also destroying his clothing); specific super-creepy examples include his eyes [[RedEyesTakeWarning turning bright red]], his forehead splitting open four ways at once and then his antennae erupting out of it, and his jaw ''splitting in half''. They had to tone the costume down a bit for his appearance in ''Series/KamenRiderDecade'', and even then, he was still pretty scary looking.
* In ''Film/{{Troll}}'', when Torok injects Peter with his ring to turn him into one of his minions, he turns bright green with slime oozing from cuts on his body while screaming in agony the whole time, morphing into a cocoon which cracks open. Out pops a little monster with Peter's facial features and spider legs.
* Using the shape-shift drug [[TabletopGame/Warhammer40000 polymorphine]] doesn't look like much fun if agent Lechias' face in ''Film/{{Damnatus}}'' is anything to go by; not to mention that just to ''start'' the process you have to stab yourself in the stomach with a big friggin' needle.
* In ''Film/HocusPocus'', we don't actually see Thackeray Binks' transformation into a cat, but we can ''hear'' his body changing shape, as well as the poor guy screaming as it happens. It doesn't sound comfortable ''at all''.
* In ''Film/TheWolfman2010'', turning into a werewolf involves a lot of snapping bones and blood from the mouth.

* The first time Dr. Curt Connors changes into the Lizard in ''Film/TheAmazingSpiderMan'', he is ''not'' having a good time.
* ''Film/GIJoeTheRiseOfCobra'': [[spoiler:Destro getting his metal face.]]
* The ''Film/Underworld2003'' universe has a variation of this ({{implied|Trope}} in the films, outright stated in the {{Novelization}} of the first movie). The first transformation into a [[OurWerewolvesAreDifferent Lycan]] is ''extremely'' painful, but it becomes much less so over time, and each individual adapts. In ''Underworld: Awakening'', Quint Lane has undergone experiments to transform him into a [[CanisMajor super-Lycan]], but an apparent side effect of the treatments seems to be that unlike most other Lycans, he can't transform seamlessly; even simply [[PartialTransformation morphing one hand into a Lycan claw]] has him visibly wincing and groaning in pain.

* Vlad's first step to becoming a vampire after he drinks the Elder Vampire's blood in ''Film/DraculaUntold''? His body shuts down and dies.
* In a variant from ''Film/{{Creepshow}}'', Jordy's gradual transformation into a mass of green filamentous space-vegetation isn't exactly painful, but it ''itches'' so badly that he can't resist immersing himself in water to relieve his discomfort, even knowing that this will only accelerate the process.
* ''Film/TheNuttyProfessor1996'': Sherman's transformation into Buddy Love is excruciating, and it causes him to pass out. [[spoiler:It is {{deconstructed|Trope}} when Jason, Sherman's assistant, discovers that the weight loss formula that Love plans to ingest is lethal.]]
* [[spoiler:John Connor's]] transformation into the T-3000 in ''Film/TerminatorGenisys''. The infection that transforms him is nanomachine-based, and introduced through ''his mouth'' when [[spoiler:the T-5000]] grabs him. The initial scene shows glowing matter penetrating into [[spoiler:Connor's]] head from around his mouth. A later flashback shows him mid-transformation, his flesh and bone being gradually turned into machines, all while he writhes in agony and the nanomachines make sickening crunching and buzzing noises. For a split second, his entire head is shown beginning to be converted.
* In ''Film/BeyondSherwoodForest'', Alina's transformation into a dragon is shown to cause her considerable pain.

* ''TabletopGame/MageTheAwakening'' features a spell whereby one can force a person to transform by forcing their new form ''to claw its way out of their normal body''.
* ''TabletopGame/{{Exalted}}'':
** Infernal Exalted have the Charm Inner Devils Unchained, which turns the target into a demon. Painfully.
** Then there's the process of becoming akuma, which throws in plenty of MindRape in addition to everything else.

* Parodied in ''Theatre/HolyMusicalBatman'' as Dick Grayson claims he can "feel his transformation beginning," as he doubles over and oddly wiggles his fingers to simulate feathers, but the "transformation" really just consists of him dramatically tearing his clothes off to reveal the Robin costume underneath.

* ''VideoGame/Persona5'' has the characters undergo both mental trauma when their Persona first awakens, and then physical as they have to really pull their mask off of them, revealing bloody faces for a bit before transforming. Thankfully, each Phantom Thief just suffers this once.

* ComicBook/TheIncredibleHulk transforms extremely painfully in most instances, which is probably why Banner's attempts to keep control tend not to work once it's actually started. In his case, the pain is mental as well, as he can feel his human intellect degenerating.

** In "I Was a Teenage Gary", [=SpongeBob=] is accidentally injected with snail plasma by Squidward to cure his pet snail, Gary. Squidward ensures [=SpongeBob=] that he'll be fine, and he believes him. But the next day, he starts exhibiting snail-like behavior, including meowing, eating snail food, and walking slowly. His fears are turned into reality as he goes through the gradual transformation into a snail.

[[quoteright:300:[[Film/AnAmericanWerewolfInLondon https://static.tvtropes.org/pmwiki/pub/images/awilchange.png]]]] [[caption-width-right:300: "''I didn't mean to call you a meatloaf, Jack!''"]]

Nothing compares to the pain I felt that day, and since then, all other pain...is numb."''

In order to [[ShapeShifting shapeshift]], every part of your body would have to twist and contort. Typically, it’s not acknowledged that would hurt...''a lot.'' In most media, shapeshifting is done quickly and without undue pain for the shifter.

* ''Physical'' - The body is tortured during the transformation process. This is rather understandable, as one would imagine the bones and organs shifting around as having some sort of impact on the nerves.
* ''Mental/Spiritual'' - The user's mind is overrun with [[MindRape horrid]]... whatever. We rarely get into a shapeshifter's head. Externally, it looks like they undergo a FreakOut every time they change shape. This may even be necessary to transform, in cases like that of ''Comicbook/TheIncredibleHulk''.

Usually not associated with VoluntaryShapeshifting, where the user generally knows enough to pick a quick and painless method of transformation. It's much more common with {{Involuntary Shapeshifter}}s and {{Baleful Polymorph}}s. That said, it can be [[GodzillaThreshold great drama]] to have a shapeshifter know a transformation will be painful but chooses to do it anyway. Done properly, it is always WorthIt.

* ''Fanfic/AbraxasHrodvitnon'': In this ''Film/GodzillaKingOfTheMonsters2019'' fanfiction, it's ZigZagged and somewhat [[DefiedTrope defied]] during [[Characters/AbraxasHrodvitnonMonsterX Vivienne Graham]]'s {{Metamorphosis}} inside San's decapitated head. She's kept comatose throughout her months-long gradual transformation, but still, in the first chapter, her spine lengthening causes so much agony that it gets through to her unconscious mind and San has to sedate her further. Later after her rebirth, Vivienne (who at this point has been through a ''lot'' of physical punishment) screams in utter agony when San's new head on her back rapidly develops its jaws.

* The remake version of ''Film/{{The Fly|1986}}'':

* ''Film/HellBoundHellraiserII'' reveals Cenobites are created from certain poor souls who solve the Lemarchand Configuration. Becoming one is as agonizing as it looks, largely because it involves your skin being split and metal inserted into your flesh. In the opening flashback Elliot Spencer's transformation into Pinhead has him screaming as the iconic pins are put in his skull. Much later in present day, Julia betrays Dr. Channard by feeding him to [[EldritchAbomination Leviathan, the Cenobites' master.]] Cue the doctor screaming as razor wire is wrapped around his head, weird fluid is shot into his veins, and some kind of weird tendril-like appendage fuses to his cranium.

* ''Film/UnderworldAwakening'': Quint Lane has undergone experiments to transform him into a [[CanisMajor super-Lycan]], but an apparent side effect of the treatments seems to be that unlike most other [[OurWerewolvesAreDifferent Lycans]], he can't transform seamlessly; even simply [[PartialTransformation morphing one hand into a Lycan claw]] has him visibly wincing and groaning in pain.

* Johnny Blaze's first transformation into the ''Film/GhostRider'' has his skin burning and melting off. He goes beyond the point of screaming in pain and winds up laughing maniacally before the process finishes. Subsequent transformation are instantaneous and seemingly painless -- unless the Ghost Rider just doesn't acknowledge pain.

* ''Film/TheMask''. The first time Stanley puts on the mask. All the times it occurs later it's off-screen, for a good reason. Though thankfully it’s a lot less painful coming off and even better The Mask is a genuinely insane but a sweet, kind hearted polite person who other than shoving exhaust pipes into the bottoms of the mechanics is pretty much harmless and wants fun most of the time. The Mask Pressbook has this to an extreme in their test images of Jim Carrey turning into the Mask. One of them looks like it was borrowed from ''The Howling'' or ''American Werewolf in London''. There are pictures of that on [[http://www.jimcarreyonline.com/forum/viewtopic.php?t=8492 Jim Carrey Online.]]

* The poor title character of the dark and edgy ''Film/KamenRider'' {{deconstruction}} film ''Film/ShinKamenRiderPrologue'' suffers from this. Rather than simply having the "armor" appear over his body, Shin's body actually changes, distorts and morphs into the Shin Kamen Rider. This is only done twice in the film, and is extremely painful for the guy (also destroying his clothing); specific super-creepy examples include his eyes [[RedEyesTakeWarning turning bright red]], his forehead splitting open four ways at once and then his antennae erupting out of it, and his jaw ''splitting in half''. They had to tone the costume down a bit for his appearance in ''Series/KamenRiderDecade'', and even then he was still pretty scary-looking.
* In ''Film/{{Troll}}'', when Torok injects Peter Dickinson (Creator/SonnyBono) with his ring to turn him into one of his minions, he turns bright green with slime oozing from cuts on his body while screaming in agony the whole time, morphing into a cocoon which cracks open. Out pops a little monster with Peter's facial features and spider legs.

*** Firstly, Johann Schmidt: he is shown injecting himself with the unfinished SuperSerum in a flashback -- fire then burns around him and it cuts to his face clearly in pain and screaming, turning into the ComicBook/RedSkull.

** ''Film/{{The Incredible Hulk|2008}}'' shows a different take on the classic Hulk-out; Here, Banner's transformation into The Hulk is ''massively'' unsynchronized, with body parts changing at different paces. In one scene, the bones in Bruce's shoulder grow faster than the rest, leaving his skin grotesquely distended for a brief moment.
** In ''Film/{{The Avengers|2012}}'', the Hulk's first transformation looks excruciating and takes a long time, because Banner is fighting it the whole time. The second time, he transforms intentionally and it only takes one smooth second, with no thrashing or screaming.

* The ''Film/{{Underworld|2003}}'' universe has a variation of this (implied in the films, outright stated in the novelization of the first movie). The first transformation into a Lycan is ''extremely'' painful, but it becomes much less so over time, and each individual adapts.

* ''Film/{{The Nutty Professor|1996}}'': Sherman's transformation into Buddy Love is excruciating, and it causes him to pass out. [[spoiler:It is deconstructed when Jason, Sherman's assistant, discovers that the weight loss formula that Love plans to ingest is lethal.]]

* Various instances in ''Anime/EtoRangers'';

* ''Manga/FullmetalAlchemist'', [[spoiler:Ling's transformation into Greed and Bradley's transformation into Wrath]]. Both instances have the subjects look like they're being ''torn apart'' and [[spoiler:Bradley]] describes it as a continuous cycle of dying and being revived until he pulls through.

* In ''Manga/DevilMan'' when a person is infected with a demonic spirit they scream in pain as they are transformed into demons.

* In ''Fanfic/{{Delusions}}'' transforming into an alicorn is painful. Celestia and Luna's ascensions hurt even more than Twilight's (which involved wings growing and a height change) did because they were originally mules. Celestia can't even describe the pain.

* ''VideoGame/FinalFantasyDimensions''

** ''[[VideoGame/TheLegendOfZeldaTwilightPrincess Twilight Princess]]'':

[[quoteright:300:[[Film/AnAmericanWerewolfInLondon https://static.tvtropes.org/pmwiki/pub/images/awilchange.png]]]] [[caption-width-right:300: Beware the moon, David.]]

In order to [[ShapeShifting shapeshift]], every part of your body would have to twist and contort. Typically, it’s not acknowledged that would hurt...''a lot.'' In most media, ShapeShifting is done quickly and without undue pain for the shifter.

Expect a lot of [[Main/AnatomyAgony Anatomy Agony]] tropes to come into play here. I.e. the character transforming might have their [[TheToothHurts teeth fall out]], their [[{{Fingore}} fingers convulsing violently]], their [[AgonyOfTheFeet feet stretching out]], etc.

-> Is that a full moon?...[[BigOMG OH MY GOD!]]

* In ''VideoGame/FinalFantasyDimensions'', [[spoiler:Vata of the Wind]] renders an intangible enemy vulnerable by allowing it to possess him. In the ensuing boss fight, half his body has been overtaken and transformed into the dark flames that made up the bodies of the Blades of Nil, while his still-normal face is locked in a grimace and he is gripping one transformed arm with his normal one as he begs the party to finish him before his mind is consumed. (It is not likely that they will, and partway through the battle, the rest of his body is overtaken.)

* The [[https://knowyourmeme.com/memes/my-metamorphosis-begins "My Metamorphosis Beigns"]] meme, where a stick figure brutaly melts into another being. However, usually the end results are [[BaitAndSwitch very unexpected]]

In order to [[ShapeShifting shapeshift]], every part of your body would have to twist and contort. Typically, it’s not acknowledged that would hurt...a lot. In most media, ShapeShifting is done quickly and without undue pain for the shifter.

* ''Manga/FullmetalAlchemist'', [[spoiler:Ling's transformation into [[FanNickname Greedling]] and Bradley's transformation into Wrath]]. Both instances have the subjects look like they're being ''torn apart'' and [[spoiler:Bradley]] describes it as a continuous cycle of dying and being revived until he pulls through.

* ''Mental/Spiritual'' - The user's mind is overrun with [[MindRape horrid]]... whatever. We rarely get into a shapeshifter's head. Externally, it looks like they undergo a FreakOut every time they change shape. This may even be necessary to transform, in cases like that of the ''Comicbook/IncredibleHulk''.

** ''Film/TheIncredibleHulk'' shows a different take on the classic Hulk-out; Here, Banner's transformation into The Hulk is ''massively'' unsynchronized, with body parts changing at different paces. In one scene, the bones in Bruce's shoulder grow faster than the rest, leaving his skin grotesquely distended for a brief moment.

* Ben's final stage of transformation into Benwolf, in ''WesternAnimation/Ben10''. For most of the episode, he'd just been gradually getting furry and wolflike, then... ouch. Of course, a lot of Ben's alien transformations in the original series look pretty painful and gruesome as he gains features such as additional limbs when becoming Four-Arms or Stinkfly, or even literally inflating when he becomes Cannonbolt.

* The ComicBook/IncredibleHulk transforms extremely painfully in most instances, which is probably why Banner's attempts to keep control tend not to work once it's actually started. In his case, the pain is mental as well, as he can feel his human intellect degenerating.

* ComicBook/{{Morbius}}:

* ''Franchise/WonderWoman'': The way people react when being turned into Circe's [[BalefulPolymorph Beast]][[ReforgedIntoAMinion iamorphs]] indicates that it is a very painful and horrific experience.

* In the ''Franchise/{{Superman}}'' comics in the late 80s and 90s, Matrix (the Supergirl of that time) was actually an artificial life-form. Shapeshifting, while being one of her primary abilities, was noted for being very painful for her.

* ''WesternAnimation/TeenTitans'':
** Most of Beast Boy's transformations appear painless, except for the episode when an accidental shower of chemicals caused him to morph into a [[ComicBook/IncredibleHulk Hulk]]-like werebeast against his will.

** The Avengers endure some painful transformations in the episode "Gamma World", as part of The Leader's plan to turn everyone in the world into Gamma-irritated monsters. ComicBook/IronMan's pain receives particular emphasis, as the animators show the toll the gamma blast takes on his shrapnel-embedded heart.
** Simon Williams' transformation into ComicBook/WonderMan, in another episode, seems unbearable as well. The other characters mention that Simon became the only person to survive the process.

* ''WesternAnimation/SpiderManTheAnimatedSeries'': Spider-Man himself undergoes this during the "Neogenic Nightmare" arc. It starts with simple bouts of PowerIncontinence, and is then followed with debilitating pain in his sides, which he describes as feeling like "getting a massage from [[WolverineClaws Wolverine]] - from the inside." Finally, he sprouts [[MultiArmedAndDangerous four extra arms]] before painfully transforming into a monstrous half-man/half-spider creature. An alternate Man-spider shows up in one of the later episodes when Spider-man has to team up with his alternates. That Peter accepted the mutation fairly well but the villain forced him to be Man-spider at the worst time. Man-spider's later fate is unknown but presumably he's back to normal.

* ''Fanfic/AbraxasHrodvitnon'': In this ''Film/GodzillaKingOfTheMonsters2019'' fanfiction, it's ZigZagged and somewhat [[DefiedTrope defied]] during [[Characters/AbraxasHrodvitnonTitansAndOtherCreatures Vivienne Graham]]'s {{Metamorphosis}} inside San's decapitated head. She's kept comatose throughout her months-long gradual transformation, but still, in the first chapter, her spine lengthening causes so much agony that it gets through to her unconscious mind and San has to sedate her further. Later after her rebirth, Vivienne (who at this point has been through a ''lot'' of physical punishment) screams in utter agony when San's new head on her back rapidly develops its jaws.

** Interestingly, the transformation gun doesn't have this effect, even on normal humans (though it is implied that it did before Tedd perfected it; when Elliot uses the transformation belt, which is based on an earlier version of the TFG, he is incapacitated for several minutes -- and his later cat-hybrid transformations reflect this as well). "Ok, I need an aspirin, a ball of yarn, and thirty-seven pounds of catnip, stat!"

[[quoteright:300:[[Film/AnAmericanWerewolfInLondon https://static.tvtropes.org/pmwiki/pub/images/awilchange.png]]]]

* ''VideoGame/Killer7'' features Heaven Smiles as its regular enemies. While some of them are transformed humans, you rarely see the transformations. When you do, they usually feature an instantaneous transformation or an offscreen one. THEN we have [[spoiler: Andrei Ulmeyda]], whose transformation goes like this: [[spoiler: The army, wishing to experiment on him to try and use Smiles as their own weapons, injects potent Heaven Smile tumors into him. The army triggers a small explosion for some reason, but then an even larger explosion occurs amd Ulmeyda asks why you didn't kill him at the injection and saying he "can't control this urge to kill." He then screams, his head then flies off his head, his acidic blood (acidic because of all the diseases he infected himself with to create vaccines) kills everyone in the army present, then his blood BRINGS HIS HEAD BACK ONTO HIS BODY AND PULLS UP HIS AFRO. Needless to say, Ulmeyda was in GREAT PAIN in his last moments of sanity.]]