"I'm afraid I didn't land very well. Fortunately I had programmed my earliest robots to save my life at any cost! They found me in a lonely alley before the spark of life had fled. [...] I shall never forget the sight that greeted me upon regaining consciousness! [...] I remember I felt well — even strong — although I had this incredible sense of detachment. And then, I lifted my hand to my face... but it was no longer my hand!"
Alphonse Elric, in Fullmetal Alchemist. His entire body is taken by the Doors of Truth, so Ed does the only thing he can and binds his soul to a suit of armor conveniently standing in the corner. This isn't actually permanent. Al gets his real body back four or five years later, at the end of their quest.
Alphonse again in a later episode of the 2003 anime continuity. Kimblee starts a chain reaction that will turn Al's armor body into a bomb. Deciding that the only way to save him is to change his composition into something else but lacking the ability to perform a more traditional transmutation, Scar gives up his arm to transfer its valuable contents to Al, making him into a living Philosopher's Stone.
In one episode of Blood+, Saya does this with her adoptive younger brother Riku. Despite herself and Haji being shining examples of Friendly Neighborhood Vampires who hunt bad vampires, she beats herself up for it. It is however slightly tragic in that he will never grow up, becoming an undead Pinocchio. Also he pretty much loses his personality, instead becoming a slave with no desire except to serve and protect Saya. Except... the true tragedy is it only kept him alive a little longer- Diva decided to rape and murder him shortly afterward.
She also did this once before by accident, on Haji. He's exactly the same as before. In fact, the reason he needed this trope is the same kind behavior afterward
Diva does this too. Some by choice, some by force. None of them had any complaints.
The entire premise of Bleach, at least for the living characters, hangs on this trope.
In the very first episode, Ichigo gets stabbed in the heart by Rukia, giving him her full Shinigami powers. Slightly averted when we are told that his father was also a Shinigami, and hence Ichigo always had those powers. Played straight when, in an effort to regain his Shinigami status, Ichigo visits Urahara , who has his Chain of Fate chopped off, and turned him into a Vizard instead... and when this isn't enough to let him defeat Ulquiorra, he becomes an even MORE powerful hollow....
In One Piece, Franky manages to rebuild himself after being run over by a train. Of course, this merely serves to make him even more Crazy Awesome.
In the first episode of Hellsing, Seras combines this with First Episode Resurrection. Alucard shoots through her, using a gun that fires explosive shells, to kill the vampire holding her hostage. He at least asks her permission before vampirising her, and this is also an exception to "never ends well" since she doesn't turn evil though she has gone on a couple of Mook killing rampages.
In Transformers Victory, a dying God Ginrai is transformed into Victory Leo, a Mecha Expansion Pack for Star Saber. He goes feral for a bit but eventually snaps out of it. (Since God Ginrai was actually a Combining Mecha formed of Super Ginrai and Godbomber, the inability to separate might have been a factor in the trauma.)
In Tsubasa Reservoir Chronicle, Fai almost dies from shock caused by the loss of an eye. He is saved by being turned into a vampire who can only feed from his love interest.
Likewise this is done for a Mermaid who had given up her voice. She broke the taboo by shouting to save them which resulting in a death curse; and a different member of the Monster Royalty gave his blood/life essence to her.
Shinkyoku Soukai Polyphonica has Prinesca Yugiri. After a fatal injury, her father's spirit combined with her, effectively making Prinesca more than human. The most noticeable sign of the change was her blonde hair turning to purple.
A less serious example would be Hazumu's transformation into a girl in Kashimashi: Girl Meets Girl. His male body was crushed after getting hit by a spaceship, and for whatever reason they rebuilt him as a female.
The strong hints that Hazumu was actually a girl suffering from Gender Identity Disorder may or may not have had something to do with this decision.
Rather sad example in D.Gray-Man. How so? Well Allen Walker out of his sadness at his adopted father's death accidently has him transformed by the Millennium Earl post-mortem, turning him into the skeleton for a human-killing machine. Said skeleton then curses Allen's left eye, before being torn to shreds by the kid's newly awoken powers.
3×3 Eyes starts with the main character, Yakumo, killed by a pet monster belonging to the last Sanjiyan (Pai). Pai saves him by taking his soul into herself, turning him into a Wu, an immortal being whose mission is to protect the Sanjiyan (if the Sanjiyan is killed, he dies). The Wu still looks human and is free-willed, but becoming one makes him a severe Plot Magnet and he must leave his friends and travel with Pai until they can become human.
In Rosario + Vampire, Tsukune gets repeated emergency transformations anytime Inner Moka isn't able to fight. Then the last attempt at an emergency transformation turned Tsukune into a crazy powerful ghoul. Oops!
There's an entire race of humans who have undergone the Emergency Transformation in the works of Leiji Masumodo, "The Machine People." Machine People can be arrogant and cruel, but they can also be wise and sad. How much of your soul cybernetics eats depends on the person and story in question.
In Code Geass, Jeremiah gets hit with it TWICE. First he's rebuilt after apparently being killed by Kallen, coming back in the first season finale with a major screw loose and angst about being mechanized. After being crushed in his mecha by water pressure at the end of the season, he returns again in season 2, upgraded further, with his sanity intact and no longer concerned with his transformation. Then he has a Heel-Face Turn and becomes even more of a Memetic Badass
A common practice in Ghost in the Shell in its various incarnations, with cybernetics being used for repairs or wholesale replacements of the body. Motoko was stated to have been one of the earliest humans saved using a full prosthetic body in this way, after she and Kuze survived a plane crash as children.
Aureolus Izzard attempted to turn Index into a vampire in A Certain Magical Index in order to stop Necessarius from inflicting the periodic memory loss on her. However, he didn't know that Touma had already saved Index from her fate.
In Black Blood Brothers, this happened to Jiro Mochizuki, when he was turned into a vampire by Alice Eve, prior to the start of the series.
In Armitage III, Ross has a artificial leg at the beginning. Later in the story more than half of his body is replaced with mechanical parts to save his life.
In Mardock Scramble, protagonist Rune Balot, a Disposable Sex Worker, is almost killed by her current boyfriend/employer in a car bomb. Dr. Easter intervenes and saves Balot's life by turning her into a technopathic cyborg. Though he was unable to save her vocal chords, so she is now effectively mute when not controlling speaker systems.
Dio Brando used the Stone Mask to become a vampire in JoJo's Bizarre Adventure Part I when Jonathan and the police had him cornered after exposing his attempts to murder George Joestar.
UQ Holder uses this as the basis of the plot: the protagonist inadvertently gets himself in the way of a bounty hunter who cuts off his arm and impales him, and his only means of survival is to drink Evangeline's blood to make himself immortal.
This is how Patriot from Young Avengers said he got his powers, via blood transfusion from his super-grandpa. He was lying. And then later it happens for real.
Jennifer Walters, attorney at law, also got a blood transfusion - from her cousin Bruce Banner. Unusually for this trope, Jen usually likes being She-Hulk or even prefers it to her human form. The later Retcon that the Hulk's personalities are a result of multiple personality disorder and were not caused by his powers happens to explain away why she doesn't have the same problems the Hulk has. Of course, she did have some issues at first (but more roid rage-ish than "HULK SMASH"). As she became more used to the transformation, her lack of inhibitions shifted themselves from wanting to break stuff to just having fun.
Steel/Commander Steel of DC - Henry Heywood was severely injured by saboteurs. A scientist gave him steel replacement parts, saving his life and turning him into a super-strong and durable "indestructible man". In the New 52"Rotworld" stories Henry Heywood uploaded himself into a robot body when the Rot was taking over the bodies of the living.
Marvel: A blood transfusion from the original (highly humanlike android) Human Torch gave Spitfire her super-speed powers. Yes, a blood transfusion from a flaming robot gave her super-speed powers. A second transfusion forty years later not only reactivated her then-faded powers, but de-aged her back to the age when she first became Spitfire.
In the Forgotten Realms comics, the character Minder was originally a dwarven adventurer who was fatally injured in battle; in desperation, the wizard of the group transferred her spirit into a magically animated golem.
Star Wars: Legacy: Cade refuses to let his childhood love Azlyn die, even though she asks him to, accepting her fate and the will of the Force. When all other options fail, he gets her to people who put her in a Vader-esque life support armor. After waking up, she was really pissed at him. Fortunately for her, she managed to avoid slipping to Dark Side and managed to get the scary black suit replaced with something much more elegant.
Bunnie Rabbot in the Sonic the Hedgehog comics had already been changed into a cyborg against her free will; however, being only half-roboticized, the effects eventually catch up with her and start screwing up her body, putting her in the hospital. She's given the option of removing her original robotic limbs (transformed from her real ones) and replacing them with new ones (which would ruin her chances of deroboticization and having her original flesh-and-blood body back, a longtime goal/dream), or trying to treat her condition to slow oncoming death. She goes for the upgrade, deciding to finally fully accept herself as a cyborg. There was another option that they could have tried, but knew it was way too risky - attempting to deroboticize her. The problem was that they didn't exactly have the original roboticizer - they had it, but Sonic damaged it when they rescued her way back when and they ended up rebuilding it to use later on. As it wasn't the original one, using it to revert her to normal would be life threatening.
When Techno of the Thunderbolts got his neck snapped, he transferred his consciousness into his pack o' gear, forming a robotic body out of it. He liked it much better than his human body.
In 30 Days of Night Eben Oleman injects himself with vampire blood in order to save the remaining survivors of Barrow.
The Biggs Darklighter comics have Hobbie Klivian repeatedly lose limbs and need prosthetics to keep being a pilot. One of Biggs' lines◊, while commenting on the strength of a prosthetic hand, is "Not like it makes up for losing your..." ...which is generally taken to mean that Hobbie lost his penis.
Inverted in an early Spider-Man comic: When Peter Parker had to make a blood transfusion to save Aunt May, he was almost completely depowered for about a week while the villains-of-the-issue ran amok. Aunt May didn't get any of his powers, either - in fact, the radioactivity in his blood later caused her further health problems during the Master Planner storyline.
But man, wouldn't it be totally awesome to see Aunt May kick around a bunch of supervillains for a week?
The Machinesmith, as recounted at the top of the page. A little later in the issue, while he is attacking with a crowd of duplicates, Captain America reasons that only one of them must hold the original's mind and the others must be directed by a computer bank that they are defending. He damages it, and all the robots fall. The sparking computer tells him that yes, his robots did program-record his mind, but into this computer; to get mobility he "microbeamed" into the bodies and he's never quite all there, so no matter how human-looking the bodies he built were, he was living a lie. And he couldn't self-terminate, so he thanks Cap for falling for his plan and helping him commit suicide. Though given some of the events before this, it's entirely possible that he was lying; his "death" here was the kind that is conveniently easy to undo in case the writers wanted him back. And in fact he was, as an Energy Being able to transfer into any electrical device.
Also happened to the Red Skull, who transferred his consciousness into the body of one of Arnim Zola's robots.
After going a few rounds with Daken, The Punisher was dead, until Morbius the Living Vampire glued him back as a Frankenstein's-Monster like being (Franken-Castle).
In the Alternative Universe series Mutant X, starring Havok in the body of a died mirror-Havok, Gambit was emergency-turned by a Storm that didn't "get over" Dracula's bite back when. It almost costs both their undead life.
In Superman, Hank Henshaw's physical body expired due to radiation exposure, but is able to transfer his consciousness into a robot body. His wife killed herself after seeing his new body and the Cyborg Superman later became a Death Seeker.
Planetary #0's story of a Wildstorm analogue to Incredible Hulk incorporates this. Here, rather than a gamma bomb, ersatz-Banner was caught in the blast of a Reality Warping supercomputer, which he had set to erase from the universe all matter within a small area of desert. A witness to his transformation into a Nigh Invulnerable monster hypothesizes that in order to turn himself into something that would survive the blast, ersatz-Banner ran through his head an equation based on the theoretical physics behind the computer's Reality Warping.
In Xombi, inventor David Kim was revived from a critical wound when his lab assistant injected him with a beneficialnanotechnological virus. In order to rebuild David, his nanites used the closest matter available, which included the lab assistant herself.
The short-lived Archie Comics title ManTech (based on a line of toys) was about a trio of dying astronauts who are found by an alien. The alien saves their lives by turning them into super-powered cyborgs. Lasertech loves the change, Solartech accepts it as necessary, and Aquatech hates it.
In Highschool Dx D, this is how another being's transformation into an angel or devil works, Issei being the primary series example.
In Hack Slash: Slice Hard, Emily Cristy's cosmetics company researched "slashers" in hopes of reversing the aging process; when the slashers escape, "slasher serum", which induces the transformation into a slasher upon death, is the only thing to come of this research. Cristy used a vial on herself after being mortally wounded by an escaped slasher. This had the side-effect of making her go absolutely crazy — they don't call them "slashers" for nothing.
This is the origin of the Human/Atomic Sub in Big Bang Comics. The aged Dr. Noah Talbot designed a sophisticated robot body as a prosthesis for injured soldiers, but when Nazis came to steal his research he suffered a heart attack and was forced to transfer his own mind into his creation before he died. It wasn't a decision he would regret, even though an oversight in developing the body's artificial "blood" meant it had to be submerged in water once every hour or so.
The Return is built on this. There are precisely two Succubae who were transformed without it being this trope, and only one of those went into it fully informed of the consequences.
John in With Strings Attached. He's hit with metamorph powder, which if left unchecked would mutate him horribly. The Fans can't neutralize it, but they can direct it into a more palatable form. After discovering he's grown wings (among other changes), he has a What Have I Become? moment for about half a day. After he throws himself over a cliff and flies, though, he's a lot happier with his new body. (Though later he finds he's been Blessed with Suck, but it's not a big problem until the possibility of going home arises.)
There are a couple fics out there based on the Ranma ½ manga only Herb Arc goes badly for Ranma, requiring one of these, such as Relatively Absent (Sailor Moon crossover in which Ranma's chosen to replace Setsuna as Sailor Pluto post Season S to keep Ranma alive after being buried in a landslide caused by the fight with Herb), or The Weapon, which has an organization rebuilding Ranma after the fight.
The Powers Of Harmony has this as an important event in the backstory: When Discord mortally wounded her, Harmony fused herself with the planet to stop him from killing her. Unfortunately, that's left her trapped ever since.
When the Changeling Princesses Cocoon and Pupa, and Pupa's pegasus friend Pilgrim were all mortally wounded in a cave-in, Cocoon's last act was to fuse Pupa and Pilgrim together, saving both their lives in the process.
The Pony POV Series Chaos Verse version of Fluttercruel was severely injured while in Oblivion, forcing Discord to infuse her with chaos to save her. As a result, she becomes a Half Pony Hybrid with similar powers to him.
In Diaries Of A Madman, Celestia and Luna have to infuse Navarone with the life force taken from a tree in order to heal his major injuries. As a result he gains several plant-like characteristics, as well as much increased life expectancy.
Disney's Inspector Gadget: ditzy security guard John Brown is "rebuilt" as a cybernetic 'super cop' after running afoul of Sanford Scolex/Claw. This results in a brief moment of What Have I Become? when Brown sputters "I'm not me anymore! I'm a hardware store!"
Apparently happened to the original Inspector Gadget...only he'd just fallen down the stairs! From a banana peel, no less.
Pirates of the Caribbean: At World's End has this happen to Will when Jack sacrifices his chance at immortality to save him from being mortally wounded.
Star Wars: Calling Palpatine an ally would be quite a stretch, but this is exactly what happens to Anakin in Revenge of the Sith to create Darth Vader. Other characters, not being quite as badly injured, get Artificial Limbs.
Doom has the main character injected with the superhuman and/or demon serum after being fatally injured in a textbook example. The treatment he took theoretically has no disadvantages associated with it, however it does run the risk of getting oneself transformed into a vicious, murderous mutant creature. Part of the explanation was that the "demons" themselves instinctively only tried to infect those with the "evil gene" or potential for evil or whatever, which is what made them monsters due to the virus/serum. So in theory, any person that the demons didn't purposely infect to turn into monsters would develop super-powers instead.
This is the origin story for RoboCop. Shot, run over and brutalized by drug dealers in his 1987 debut, Officer Murphy would have died from his injuries... should have died from his injuries... if it weren't for the Detroit Police Department having a deal with OCP, who as part of a drive to manufacture a police force capable of dealing with the rampant crime decided We Can Rebuild Him. The result? Only parts of his upper torso are still organic, part of his brain has been replaced with computers, and he has problems feeling and even recovering his free will. One amazingly cruel scene has one of the doctors mention they could save one of his arms, but the Corrupt Corporate Executive blithely orders it lopped off (although there is Fridge Brilliance here: leaving the biological arm on would mean a lot more meatware to have to support on the damaged digestive system, would have resulted in imbalanced strength and maintenance-one arm has a titanium grip and can be upgraded with a trip to the machine shop, the other doesn't and must be exercised, not just repaired-and would have looked even creepier due to the lack of symmetry). Amazingly, his dedication to duty allowed him to survive the change, recover his humanity and make impressive crime busts, even managing a Zeroth Law Rebellion with a little help from an OCP executive.
Happens in the prologue to Dragonheart, in order to save a dying prince.
In Underworld, this trope is played straight in an unusual format: Selene bites Michael to save his life. Strange in that Michael was already a werewolf, and he was dying from being shot by silver bullets. The bite then turns him into a werewolf/vampire hybrid.
Subverted in Avatar: When Dr. Augustine is mortally wounded after being shot, she and her avatar are brought to the Tree of Souls with the purpose of transferring her consciousness permanently into her avatar. However, the transition fails as her human body is too gravely wounded. It does, however, succeed with Jake at the end of the film.
Twilight Edward turns Bella into a vampire after she almost dies from childbirth. They always planned to transform her eventually when they married, but her Surprise Pregnancy ultimately drove those plans. This goes for the others as well, since Carlisle only ever changed people who would have otherwise died for sure, because he didn't want to condemn anyone to his immortal existence.
Also, Alice was transformed to save her from a hunter-vampire, and Esme was changed after an almost-successful suicide attempt after losing her only son. Carlisle and Jasper however, were not.
This also happened to Edward. In 1918, at age 16, he and his mother were dying from the Spanish flu. She took him to Carlisle, begged him to save Edward at any cost, then died.
In The Two Princesses of Bamarre by Gail Carson Levine, the cure comes too late for Meryl, who has to be turned into a fairy, and it turns out this is also what happened to legendary epic hero Drualt.
Not only Jesse received this. Even though Marius had planned to make Armand a vampire anyway, he didn't want to bring him over as early has he had to when Armand was about to die from a stab wound with a poisoned blade.
And in The Vampire Lestat, Lestat's first vampire offspring was his mother, to save her from death by tuberculosis. She more-or-less gave her consent beforehand and, arguably, took to vampirism better than Lestat.
Subverted in a manner with Claudia in Interview with a Vampire. Wracked with guilt over his own recent transformation, Louis is wandering the backstreets alone when he finds a little girl who has just been made an orphan by the plague. Desperate with hunger, and thinking he can perhaps grant her the mercy of a quick death rather than catching the plague or starving to death on her own, he feeds and takes her to the brink of death. Lestat then pops in and, deciding it would be fun to have an eternal vampire daughter (not to mention something/someone to help bind Louis to him), he turns her. Louis spends years (if not decades) blaming himself for taking her mortal life, and while Claudia forgives him (she sees vampires as predators and thus has no moral problem with him having killed a human girl), she comes to hate her other "father" Lestat for making her an eternal child.
SookieStackhouse is given Vampire blood to save her life rather than to bring her all the way over to the vampire side. In fact, drinking Vampire blood is a drug addiction thing in this/these series, because it enhances humans temporarily.
In the Blood Books series, this happens to Vicki. Not in the show, though.
Interestingly, this is averted sort of in Anno Dracula by Kim Newman — there's descriptions of vampirized people who had syphilis in life still showing the symptoms and, oddly, tubercular vampires still coughing blood.
The same novel has a scene where Genevieve attempts to perform this on a friend who has been fatally wounded in an attack, but the friend chooses to die rather than become a vampire.
In Fred Saberhagen's The Dracula Tape, Dracula turns Lucy Westenra to save her from death at the hands of Dr. Van Helsing, who's been stubbornly giving her blood transfusions in ignorance of blood types.
In LJ Smith's novel Secret Vampire, Poppy is diagnosed with pancreatic cancer, which is rare, painful, and inoperable in her case. Her options are death and vampirism. Her childhood friend James does the honors.
There's a scene in one of Mercedes Lackey's Heralds of Valdemar books that would qualify, where a woman (a disembodied soul trapped in the body of a bird, actually) is transformed into a spirit being rather than fade away in the bird's mind.
In addition, the Sword Need is revealed to have been created when the blacksmith forging the sword's village was attacked. She impaled herself on the blade that was in the vice, and awoke inside the sword. Eventually set free during a Heroic Sacrifice.
All of science fiction author Jack Chalker's works seem obsessed with transformation and body swapping, and this kind of "rescue" appears in more than a few, with the ur-example being Nathan Brazil's soul transference from his dying body into a deer-like creature in ''Midnight at the Well of Souls''.
Subverted in the Betsy the Vampire Queen series: Jessica, Betsy's closest friend, is suffering from severe blood cancer. She makes it very clear to Betsy that under no circumstances is Betsy to vampirize her. The cancer is eventually cured via Deus Ex Ancient Vampire Power.
C.L. Moore's classic story No Woman Born concerns an actress whose brain was transplanted into a robot body after her body was irreparably damaged in a fire.
The main character of Peter Dickinson's Eva gets in a terrible car crash and wakes up in the body of a chimpanzee. A bit of a subversion, because she actually adjusts to her new life quickly after the initial shock. She eventually chooses to live out her life in the wilds with more conventional chimps.
A variation in The Last Unicorn: Schmendrick decides the only way to save the Unicorn from the Red Bull is to change her into some other creature. Then the Bull will have no interest in her. Thanks to the random effects of his magic, he winds up changing her into a human - and she does not react well.
Inversed in the vampire romance novels of Kerrelyn Sparks, here reacts a character astonishingly well to her new vampire form, although she hates vampires with a passion and no-one else believes her that she is fine with the way she is now.
Kerrelyn Sparks Love at Stake series also contains Gregory, a youthful vampire who was emergency turned by the main protagonist of the first novel. His own mother, now an elderly personal assistant to the main protagonist, even begged that he would be saved - thus creating the first vampire that never had to bite someone to survive.
later, another (side-)character is emergency turned but thinks it is awesome, because he's got superpowers now.
Inverted in Xenocide: as the setting's version of the Internet is brought down, it threatens to bring the artificial intelligence Jane along with it. The only way she can survive is by taking a human body... and afterward, even though it's possible, she doesn't want to go back to being what she was before.
Happens to the antagonist character, Skade, early in Redemption Ark, who gets her body sheared in two. Unwilling to give up, she has her head cut off and attached to a life support system that she can plug into a robot body.
She chooses this over getting a nice new human body because she is impatient, desirous of being more resilient to the harsh conditions on her ship, and a little bit... differently sane. It also helps that it makes her extra scary. She gets a new organic body before the sequel Absolution Gap occurs, though for other practical reasons.
Happens all the time in Animorphs, since there, transformation is (usually) temporary and completely rebuilds your body, both to and from a given form. And the Animorphs find themselves in plenty of life-threatening situations.
In this case "All the time" means several times per person per scene in the later books.
Mostly because the prosthetics in the book are more "realistic": He can't see through his bionic eye, though it can act as a micro-camera; his bionic limbs carry limited and unfamiliar sensation; and he only has 'super strength' in his grip, and in some forms of striking. Though he can run at tremendous speed almost indefinitely, and has a broad variety of built in equipment.
In the Star Wars Expanded Universe, this happens to Jedi Callista Masana twice. Once when she's dying and transfers her consciousness to a ship's computer in order to continue her mission, and then again 30 years later when the ship is about to self-destruct and Jedi Cray Mingla—who is suicidal—offers her body so Callista can escape the computer. The first time is just better than death, but when she loses all contact with the Force after the second transfer, there is much angst.
Also subverted in the same book 'Children of the Jedi'. Cray's lover and fellow Jedi Nichos Marr contracted a fatal disease and Cray attempted to transfer his consciousness into a droid body using alien technology. However, the result was merely a droid programmed with Marr's personality.
"A long time ago, back at the Battle of Endor, the frigate I was working on as a doctor was hit by an Imperial barrage. Blew out whole sections of the hull, sucked crewmen out into hard vacuum. I was hit by a falling beam superheated by laser fire. One minute I'm helping a pilot with a concussion, the next minute that pilot's been dead for two weeks and I'm just waking up with a mechanical half a face and a mechanical leg. Ever since then, no woman has looked at me with any sort of serious interest. [...] Something died when I was hit in that medical ward, and I think it was my future. I think people, maybe only women, can just look at me and say, 'There's no future in him.' [...] There's no mechanical replacement for a future, Face. And every time I take a hit, and they have to cut away another part of me and replace it with machinery because I'm allergic to bacta, every time that happens I seem to be a little further away from the young doctor who had a future. He can't come back, Face. Not all of him is here anymore."
Some other characters also get cybernetics, but they tend to be more along the lines of Artificial Limbs and sometimes eyes.
In the Mercy Thompson series, this seems to be the backstory of at least one out of every three supernaturals.
In Moon Called, Dr. Carter Wallace is dying of cancer, and his son persuades him to undergo the Change to werewolf. His magical new immune system zapped the cancer and made him look thirty or forty years younger. Unfortunately, surviving as a werewolf requires psychologically accepting your new state, which the good doctor is loath to do.
The backstory of Charles's mother, mentioned in Moon Called and explained more thoroughly in Alpha and Omega, is that she was dying when a werewolf found her, fell instantly in love with her, and Changed her into a werewolf so that she would survive.
In Blood Bound, Mercy meets vampire Stefan's flock of human blood donors, most of whom are dying of cancer or drug addiction. The longer they donate to a vampire, the more powers they gain and the easier it is to turn them to vampires themselves.
This trope is used moderately with in Neil R. Jone's Professor Jameson stories. The Zoromes, a race of octopus-like aliens, transfer their brains into cyborg bodies when they near death (they also transfer well-preserved brain of the deceased title character). The transformation is portrayed as dulling the emotions, so Zoromes prefer to live a full life before being transferred. Occasionally a younger Zorome is fatally injured, as in the story Zora of the Zoromes and is transferred early. This is portrayed as very tragic, especially when two Zoromes who were very much in love are transferred prematurely, and then no longer feel anything for each other. On the other hand, the Zoromes don't seem to care if someone wants to transfer early, several aliens do so and join the crew of a Zorome ship in another story.
In the second Empire from the Ashes book, Dahak secretly arranges for his consciousness to reawaken in another starship when his original body is destroyed in a pseudo-Heroic Sacrifice, which he wasn't sure would even work.
In a less life-or-death example, Sheen the self-willed robot from Piers Anthony's Apprentice Adept novels becomes inert when she crosses over from the scientific world of Proton to the magical world of Phaze. The Brown Adept animates her as a golem, allowing Sheen to function in Phaze.
In Skinned by Robin Wassermann, the main character Lia gets into a fatal car accident. To save her, her brain is uploaded into the body of an android. This is very rare, but it happens in her future world. These people are shunned because they look too perfect. The Christian church believes these people are abominations and do not deserve to exist, because they mean science is "creating life".
In Greg Egan's Diaspora, the Earth is about to be hit by the lethal shockwave from a neutron star collision. A pair of AIs (essentially translated humans) don robot bodies in order to offer last-minute help: let them shoot people with a lump of nanoware that reads their brains while eating them. They can live on as software, escape from the kilos of meat they can no longer protect. What a choice.
A variation in the Night Huntress books, when Dave is brought back as a ghoul some time after he died because Cat inadvertently started the process when he was dying and when Bones comes back he helps the team finish it.
In the Night Watch series, the vampire Kostya became that way because he was dying of TB as a child, and so his Friendly Neighborhood Vampire father cured him by making him a vampire. Similarly, in Twilight Watch, Anton encounters a pack of werewolves and finds out that two of the members are young children who were bitten by the leader, an older guy, to save them from death, and is a loving Papa Wolf (pardon the pun) toward them.
Inverted later, when a friendly werewolf (one of said kids, by the way) takes a magical bullet for Anton while in wolf form. With her last dying breath she transforms back despite his protest that as a wolf she has a better chance to survive, but she prefers to die as a human.
Quantum Gravity: Lila Black came back from Alfheim missing...well, most of her body. She was given the choice to survive or deal with being legless, armless, eyeless...you get the picture. She became aCyborg.
In Monica Hughes' Keeper Of The Isis Light Guardian makes genetic modifications to Olwen to help her survive the planet's harsh conditions.
In Amy Thompson's The Color Of Distance, a scientist crash-lands on an inhospitable alien planet, and the Sufficiently Advanced Aliens who find her unconscious body transform her into one of them to help her survive.
In Lynsay Sands's Argeneu and Rouge Hunter Series, this is the most common reason for the vampire-like immortals to "turn" others. It is occasionally played for laughs when it turns out that the danger they were "escaping" was all in their heads, though other times it is a serious matter as the turnee is brought near death by some outside force, such as a crazed geek with an axe, or a rival immortal seeking revenge by hurting the one closest to them.
In The Sex Gates, Lee, Donna and Russell are forced to push Rita through one of the titular gates after she is stabbed, saving her life at the cost of turning her into a man. Lee accidentally falls through as well, turning into a woman. Especially tragic since Rita was pregnant at the time, and unborn babies don't survive the transformation.
In Max Barry's Machine Man, Dr. Charles Neumann goes to sleep a paraplegic and wakes up a Man in the Machine. While not a *personal* emergency, Better Future needed SOMEONE equipped to defeat the cyborg Carl, who had run amok.
In The Dresden Files, Harry accepts the mantle of the Winter Knight because his back was broken. This has far-reaching effects, the least of which being that he is now weak to iron and has to obey thresholds and other fey things.
The Red Court can do this to people. Only for them it's more that they shed their human-esque disguise.
Some werewolves can do this. (The Alphas can't, they only have a Healing Factor).
The Secrets of the Immortal Nicholas Flamel has Joan of Arc getting a blood transfusion from the vampire Scathach. It doesn't turn her into a vampire, but it does make her immortal, which explains what she's doing in a series that takes place in the twenty-first century.
Siegfried's bird companion in The Sleeping Beauty isn't dying, but gets an emergency (and permanent) transformation into a firebird because it's the only way Siegfried will be able to get through the wall of thorns. Lily is worried that the bird will see this as a Baleful Polymorph, but the bird's delighted.
It happens three times in the Den of Shadows series. First in Demon in my View, Jessica is turned into a vampire so that Aubrey and Caryn could heal hear more effectively. Then Sarah gets turned into a vampire in Shattered Mirror. Finally, in Persistence of Memory, Sassy puts his blood in Erin's veins to turn her into a hyena shapeshifter in order to save her life.
In the distant Back Story of Buffy the Vampire Slayer, the Master did this for Darla as she lay dying of syphilis. Then on Angel, a human-again but still dying Darla tries to get Angel and other vampires to turn her again.
Later but still in the Back Story, Angel is stuck on a submarine and the only person who knows how to repair it is fatally stabbed by an escaped Nazi prisoner, so Angel makes him into a vampire.
Also, Cordelia is turned into a part-demon by Skip to avoid her being killed by her visions. However, other than some glowy effects and unusual powers, this doesn't actually manifest itself too much, and she becomes a "higher being" soon afterwards.
One could argue that a variation on this happens to Illyria: the gang needs to remove some of her power before she goes supernova and destroys the whole world. She is, of course, none too pleased when the procedure works.
Also, in the Buffy episode "Lie to Me," a childhood friend of Buffy's tries to get Spike to turn him before he dies of a brain tumor. Spike does so, but he's staked by Buffy upon resurrection.
Averted in the Season 7 episode "Get It Done", in which the Shadow Men attempt to give Buffy the strength to defeat the First by infusing her with the essence of a demon. Buffy emphatically refuses with a What the Hell, Hero?, and then soundly kicks all three of their asses.
Also Backstory, shortly after Spike is turned, he goes home and turns his mother, as she is dying anyway. It does not go well.
Also, Time Lords' regeneration abilities that kick in automatically when they're about to die, though they don't get any more powers by regenerating. At least, not in the televised series (though they do have a lot of energy flowing through them in the early stages, according to "The Christmas Invasion" and "Let's Kill Hitler"); there's a reference in one of the Eighth Doctor Adventures books to Time Lord soldiers who had "force-regenerated themselves until their skins had been covered in black organic blast-proofing".
The Eighth Doctor Adventures two-part story Interference by Lawrence Miles featured a Gallifreyan priest who had been given an extremely early version of regeneration tech. As a result, his future lives included a shapeshifter, a cyborg, a heavily scarred man, a freak with a very large head, a serpent-woman, and a little grey thingy that was apparently wired directly into Time. His thirteenth life was basically an Eldritch Abomination that became a planet's entire ecosphere.
The Saxon Master subverts and averts by choosing death over regenerating and being a prisoner. Of course, he had a plan to get better in a different way, it turns out.
It also happens in the "Rise of the Cybermen"/"The Age of Steel" two parter when Mr. Crane destroys Lumic's life support system, and the Cybermen convert Lumic into the Cyber-Leader to save him, ignoring Lumic's demand that they wait till they run out of other options.
Another angle is given in the episode "Dalek", where the namesake wants to die rather than live with human morality.
On Forever Knight, Nick acceded to Natalie's request to vamp her brother when he was fatally shot. It didn't go well.
On Power Rangers Time Force, this was revealed to be the origin of Frax, Ransik's right-hand 'bot. Frax had been Dr. Louis Fericks, a scientist who had temporarily cured Ransik of a poison that was slowly and painfully killing him by administering a serum he had created. Ransik thanked Dr. Fericks for the serum by blowing up his laboratory, seemingly killing him. Fericks survived (barely), and rebuilt himself as a robot, then began his plan to get revenge on Ransik.
Meanwhile, Mesogog's right hand man Zeltrax was saved by Mesogog himself in this manner.
In the Deep Space Nine episode "Life Support," Vedek Bareil is seriously wounded in an assassination attempt while concluding negotiations for a permanent peace treaty with Cardassia. Dr. Bashir keeps him alive using increasingly extreme measures while he talks Kai Winn through the finalities, ultimately replacing a large portion of his brain with cybernetic implants. The operation has the effect of removing most of his personality, and he only survives long enough to complete the negotiations.
This was also part of Dax's The Nth Doctor in the last season. Ezri Tigan was the only un-joined Trill available at the time, so they did an emergency implantation to save the symbiont and created Ezri Dax.
Stargate SG-1 (of course) had instances of this, when characters stricken with fatal injuries or diseases had the option to become a host to a Tokra symbiote. In one notable occurrence, the character in question was dead set against the idea, but when the illness progressed far enough, they went ahead with it anyway.
Subverted on Moonlight, of all shows. Josh is shot, and Beth begs Mick to turn him into a vampire, but Mick refuses, and Josh dies. This weighs on Mick and Beth's relationship for the rest of the series.
Mitchell is faced with this twice in Being Human. In an early episode, he is confronted with a dying colleague in an alleyway. George begs him to save her. He does nothing. In the next scene, when George is asked "Why didn't he save her?", he replies "I think he did." In a later ep, he does this for an injured boy.
The Outer Limits revival episode "Music of the Spheres" has aliens subjecting the whole of humanity to signals that people think are music, but causes mysterious changes. Instead of the Cruel Twist Ending the series is known for, it turns out it's an Emergency Transformation into bald, large-headed, golden-skinned creatures, so that they can survive an impending shift in the sun's radiation. The aliens' process initially only works on people close to puberty but once the humans figure out what the hell is exactly going on and why they manage to enhance the process so that it can be applied to anyone. Some of the characters refuse to go along with the transformation; as one of our main characters puts it, he wants his wife to be able to recognize him in Heaven.
Now and Again Michael Wiseman is killed in a subway accident but secretly given the chance to have his brain placed inside a genetically bio-engineered body with superhero like abilities.
Supernatural plays with this when, in the first episode of season 9, Sam is dying and Dean makes the decision to let an angel use his body as a vessel in order to save his life from the inside.
The eponymous character in The Doctor's Wife by Clockwork Quartet has parts of her body being shut down by some unnamed malady while the Doctor has to keep replacing them with mechanical bits.
In Seisen no Iberia, Layla (dying from an arrow through the chest) is given the choice by a sealed demon to either die as a human or live on forever as a demon - provided she frees him, of course. She chooses the latter. Strangely enough, freeing a murderous demon turns out to be a phenomenally good plan.
The Shadowrun second edition sourcebookCybertechnology has a framing story that involves a badly injured runner being transformed into a "cyberzombie" (i.e. being loaded up with enough cybernetics to kill him, with only incredibly powerful magics actually keeping his soul bound to his body). Game stats for the transformation, and for a ton of cybernetic gear, are given between paragraphs of his descriptions of the horrors of the transformation.
Generally averted in the Ravenloft setting, where becoming a vampire or lycanthrope is typically regarded as a fate worse than death. An ailing Anna refused Jander's attempt to transform her in the novel Vampire of the Mists.
In Warhammer 40,000, in the rare event a SpaceMarine sustains injuries too grievous for his robust physiology to recover from but which aren't enough to kill him, he may be interred with an armored life-support sarcophagus, allowing him to pilot a walking tomb/tank called a Dreadnought. Such warriors are venerated as their chapter's greatest heroes and wisest leaders, allowed to slumber away the centuries when their skills aren't needed. Bjorn the Fell-Handed is the most famous example, a Space Wolf who fought alongside the Emperor during the Great Crusade ten thousand years ago.
The Eldar have adopted this on a racial scale - every one of them wears a Waystone at all times, which will capture their soul upon death and allow it to be placed within their Craftworld's Infinity Circuit for all eternity. It's not a true afterlife, much less a paradise, but the alternative is having their soul consumed by the Chaos God Slaanesh. In dire emergencies an Eldar's soul may be recovered from the Infinity Circuit and used to pilot a Wraithguard or Wraithlord construct in battle, but the Eldar view this practice as akin to necromancy, since it's irreversible and means that the pilot's soul is lost if its Wraith- construct is destroyed.
Dungeons & Dragons has the spell Raise Dead, which costs 5,000 gp to cast. If you can't afford that, there's the 1,000 gp spell Reincarnate, but you probably won't come back the same race, and you might come back as something that normally isn't even intelligent. For some reason, this also makes it so Baleful Polymorph is insufficient to turn them back.
On the other hand, before the Reincarnate Table was updated, you could come back as unbelievably broken things including, say, Dragons, Beholders, Demons, or just about any other monster you run into. Games with druids able to cast Reincarnate turn into a 'Hey lets keep killing me until I get to be an awesome race' sessions.
Whether polymorph cannot reverse it is a matter of opinion, since the game says nothing specific about that. If it did, though, the polymorph could still be dispelled.
In Aberrant, it's a well-established fact that an Eruption can be triggered by placing yourself in a deadly situation, and hopeful Nova-wannabes try to orchestrate specific situations to get just the right powers (jumping off a plane is popular because flying is awesome). The most commonly-mentioned downside is that you might get lame and/or stupid-looking powers instead. Strangely they don't much mention the fact that potential for Novahood is rare, and most people who try this tactic end up dead instead.
The Paragons setting for Mutants & Masterminds has a situation similar to Aberrant, though the "spark parties" and "origin chasers" tend to have unfortunate results. The page illustration is a girl looking at a newspaper article about the hero Blaze whilst soaked in petrol and what looks from the empty bottle nearby to be drain cleaner and holding a lit match.
In the musical Wicked Elphaba turns Boq into a Tin Man after Nessa literally destroys his heart and Fiyero into a Scarecrow while the soldiers are torturing him, saving their lives.
Fatima, the Voice with an Internet Connection in the PC game Anachronox was originally the main character's secretary until she died in a car wreck. The protagonist couldn't live without her, so he had her digitized.
Asellus, of SaGa Frontier is run over by a carriage before the game starts and given a Vampiric Blood Transfusion Mystical Blood Transfusion by Charm Lord, turning her into a half-mystic.
In addition, Red is turned into a Super Hero after the first battle with Shuzer, as he would have died otherwise.
In the Bad Ending of Pikmin, Olimar does not repair his rocketship in time and his supply of whatever it is he breathes instead of oxygen runs out, so the Pikmin save him by transforming him into one of them.
Especially interesting, since it is actually foreshadowed in the game!: One of Olimar's journal entries states that he would actually want to become a Pikmin, since his boss is not exactly a nice guy. He however suddenly changes his mind, when he remembers having a family waiting for him.
In StarCraft, Protoss warriors who are mortally injured are transplanted into Dragoon exoskeletons, where they can continue to fight. However, they volunteer for this, and so tend to be pretty stoic about it. Their people praise them for their devotion.
Happens to Samus in the intro of Metroid Fusion. After being attacked by an X-parasite, she's transfused with Metroid DNA to stop the infection. Unfortunately, since Fusion is chronologically the last game in the franchise, the long-term effects of such an operation (both physically and mentally) have yet to be shown.
A variant on this trope is a recurring theme in the Suikoden series: True Runes are almost always acquired by someone who needs to use its power to escape from a deadly situation, put up a decent fight against an overwhelming foe, or keep the Rune itself out of the hands of those who would misuse it. They often learn to regret this decision.
Bonding with a dying human host by a usually injured Kheldian is the canonical usual origin of the Peacebringers and Warshades in City of Heroes.
In the LucasArtsAdventure GameThe Dig, the team discover "life crystals," which have the ability to heal wounds and resurrect the dead at the cost of being literally maddeningly addictive, as evidenced by Brink's slow decent into insanity. Robbins makes Low promise that if anything should happen to her, he won't use the crystals to revive her.
Unsurprisingly she ends up dying in the process of saving the day. If you finish the game without her, she thanks you for keeping your promise when the aliens resurrect everyone (madness free). However, if you ignore her wishes and bring her back yourself, she's horrified and immediately throws herself off a cliff. When she's brought back to life at the end of the game, she's still pissed at you for that.
The titular character of the Mega Man Battle Network series was born with a fatal heart defect and used as the guinea pig for his father's and grandfather's experiments in Brain Uploading. Ten years later, he was given as an "AI" partner to his own twin brother. This plot point was never brought up taken out completely in the anime.
In Ever17 at the end of two/three routes Tsugumi shares her blood with Takeshi, You, the Kid and eventually Coco. She's the hesitant one as while it's supposed to only be so they get her antibodies, it could give them the Cure Virus and make them immortal, unaging, have aHealing Factorand see in the dark. And also potentially have a bunch of people try to capture them for research... So at the end of the story about three fourths+ of the cast is immortal.
In Super Paper Mario, Tippi was originally a human, and was turned into a Pixl by Merlon in a desperate attempt to save her life.
Rachel has done this, possibly twice in BlazBlue. First to save a mortally wounded and time-displaced Jin by installing him in the Susanooh Unit to become Hakumen. It's also possible that Ragna would have bled to death after losing his arm in the orphanage attack without Rachel biting him to transform him into a half-vampire.
In Quest for Glory II, Julanar is a woman who, while fleeing from brigands, is discovered by a djinn who transformed her into a tree in order to save her from her pursuers.
Given the themes of the series, this crops up in the histories for a number of characters in the Deus Ex franchise.
In the original game, this trope was part of the back-story for how Agents Hermann and Navarre became mech-augs.
At the end of the tutorial mission in Deus Ex: Human Revolution, Adam gets the shit kicked out of him and then shot, brought to the very brink of death. To keep him alive, he's augmented - turned into a cyborg - by his boss and the company he works for. They replace his arms, legs and heart and stick machines into just about anything you can stick a machine in. When the gameplay kicks in again, he's very different.
Notably, only the arm and chest replacements were necessary for him to survive. The rest was his employer using his contract to gain power of attorney ("I never asked for this").
The whole naga race is the result of an Emergency Transformation .
At the end of Half-Life 2, Doctor Breen is protesting being put into a "host body" as the only way to survive teleportation. Speculation is that he is one of the slug-like Advisors that attacks Gordon and Alyx throughout the Episode sequels.
Although he probably dies when Gordon damages the teleporter.
Gauldoth Half-Dead in Heroes of Might and Magic IV. During the armageddon which destroyed the old world he attempted to save himself by undergoing a ritual of lichdom. Because he was only an apprentice necromancer, he emerged from the ritual with one half of his body as that of a living human, and the other half zombified.
In Front Mission, Driscoll is part of an experiment into using the brains of human soldiers to create advanced computers. After his death, he is resurrected and serves as a component in the Humongous MechaFinal Boss.
On the same character route is when Sakuya's power is not enough to transform Kei, so both of them become Ohashira, replacing Yumei. Quite close to being Together in Death. Yumei does feel sorry for them.
In Eleven Eyes -Resona Forma-, we see that this is how the Black Knights were created. Liselotte thoroughly beat all of them except for George, who finished sealing her before he died, and Misao, who clothed her partners in armor made out of dark spirits, turning them and herself into Liselotte's guardians.
Dragon Age: Origins has the Dalish Elf Origin. Basically, your character becomes tainted and has to undergo the Grey Warden Joining in order to have a chance of survival.
In Dragon Age II, if you take your sibling with you for the Deep Roads Expedition, they will contract the taint, and the only way to save their life is to have them undergo the Grey Warden Joining. Hope you brought Anders with you as well, as he's the only guy who can lead you to the Wardens.
F.E.A.R. 2: Project Origin has a variant of this when Beckett is surgically implanted to boost his psychic abilities and link him to Alma. However, while the transformation is an emergency, it is not intended to save the patient's life, but rather to draw Alma's attention toward Beckett after she has escaped containment, in order to keep her distracted and ultimately lure her into another containment device to seal her away.
In one ending of Duel Savior Destiny Taiga becomes the Messiah and to avoid the terrible consequences this would cause Rubinas stabs him in the heart and turns him into a homunculus like herself. He seems okay with it, though it took him rather by surprise.
In the Good Ending of Fate/stay night's Heaven's Feel route, this happens to Shirou in order to save his life. Shirou is pretty much dead on his feet, with his entire body having been turned into swords from the inside out, so Ilya uses the Third Magic to transplant his soul into... something else (it's never really said what). In the epilogue, he's been put into a magically-created artificial human body, but it still needs further refinement, and Rin is seeking out Touko Aozaki for that purpose.
Both werewolves and vampires in Sorcery 101 have extraordinary resilience compared to humans, making them candidates for this trope. So do humans magically linked to vampires, called "blood bonds". In the main protagonist's backstory, he was seriously injured fighting demons. His best friend Brad knew a vampire named Seth, and asked him to help, so Seth made Danny a blood bond. Danny seems to be OK with this in general (immortal, can't get sick or gain weight, can't bleed to death, stuff like that), but isn't happy about having to deal with Seth.
A more recent example is that of Brad turning his new boss's daughter into a werewolf upon request, as she was bedridden and dying of some illness.
One of the older patients of The Dragon Doctors from the webcomic of the same name turned herself to stone to avoid dying of thirst. Thing is, she couldn't willingly revert on her own. She had to wait for someone to find her to undo the transformation—locked away in an abandoned mine, behind a magical forcefield, in the middle of nowhere. Sanity was... something of a concern.
In the same arc, when a crystalline girl is injured, Sarin changes her into a human because it's easier to heal; it's reversible, though.
And still more recently, we discover that the person who bankrolls our heroes ended up with a condition that caused her to age quickly enough that even the easily available youthening magic of the setting couldn't keep up... so they turned her to stone (as per the above example) except that she had a psychic communicating with her whenever she needed it which not only kept her sane, but allowed her to run her parents' business. After the discovery of a sapient crystalline species, Sarin was able to turn her into such as a vastly superior alternative (since that species has no aging).
One of these occurs in the first chapter of Coga Suro 2, but a slight variation in that John is transformed into... whatever that is in order to save himself and a girl after they're both swallowed by a giant maw.
Done to the character Dark Eyes to save her life in Magical Misfits, magically mixing in genes from many different other species in the process that rendered her sterile. Temporarily.
In Drowtales, Kiel'ndia is fatally poisoned and would have died if Kharla'ggen hadn't insisted that Larvova heal her. Since it's a bad idea to tell Kharla'ggen that she can't have what she wants, Larvova is forced to take drastic measures. This is the result. Kharla'ggen, being a somewhat odd individual, thinks that Kiel'ndia is lucky since she still has one of her original eyes. That's all she has left of her original body.Or not, since it was All Just a Dream.
In Death and the Maiden, Death tries to heal Mercedes's tuberculosis (caused by a run-in with Pestilence) and in doing so, accidentally turns her immortal. Then he later realizes he didn't just make her immortal, he turned her into Death.
In The Order of the Stick prequel Start of Darkness, Xykon willingly undergoes the transformation into a lich after contact with a magical disease robs him of his magical abilities.
In College Roomies from Hell!!!, when Marsha is pushed off the roof by Chester, she escapes by... spontaneously growing bat wings, suggested to be a latent effect of a radioactive "batato" that had earlier bitten her. Since half the cast had long since undergone similar transformations (without the emergencies), she adapts fairly quickly.
In MSF High, it's generally understood that anyone who goes to Nurse Keiri's office will be leaving as a female of the species easiest to treat, and she'll be doing everything in her power to keep them that way. The backstories of many Legion end similarly.
This happens in Modest Medusa. The boy who lives with Gorgon starts turning into a monster, so she saves him by turning him into a horse.
The origin story of Hive in the Whateley Universe. Sam Everheart is dying from injuries, and the nanotechnology he's been exposed to rebuilds him using the only untainted DNA nearby, from a lock of hair belonging to his deceased daughter.
MSF High Forum: Too many examples to list. The Nurse's Office is the main cause of this. Often subverted, as the office has used it for non-dangerous transformations.
At the end of The Cartoon Man, Karen is mortally wounded, and Roy saves her life by using black ink to transform her into a human cartoon.
In Chapter 27.5 of Worm, Taylor uses Lab Rat's device to undergo a temporary transformation into a monstrous, insectoid form after suffering lethal injuries at Scion's hands.
Insofar as a steam engine can actually need one of these, Henry gets one in season 1 of Thomas the Tank Engine after his crash with The Flying Kipper. Turned out for the best, since the locomotive works took the opportunity to perform some upgrades; he didn't need Welsh Coal anymore afterwards and was strong enough to pull express trains single-handed.
Exo Squad used this for the ultimate emergency, death. The brain-scans of deceased troopers were downloaded into customized human-looking but internally Neo Sapien bodies. Started as a Trojan Horse plot by Phaeton, but it worked so well that the humans soon saw the obvious benefits. The only downside is that there have to be recorded memories from an Exoframe brain jack to transfer.
And despite their clear, obvious, and constant treachery, Hackle keeps collecting their battered remains and rebuilding them.
This is the backstory of Evil Con Carne. After his body was destroyed in an explosion, Major Dr. Ghastly attached his brain and stomach to a bear.
In the final season of Darkwing Duck, Taurus Bulba is revived as a cyborg by FOWL. He's... not exactly happy about it. Of course, fitting the big guy, rather than angsting about it at all, he just gets pissed.
Bionic Six starts off with the titular family being exposed to radiation, with only The Professor's conversion machine available to save them.
Prior to God Ginrai's Emergency Transformation in Transformers Victory, Spike Witwicky is a temporary example in the aptly titled "Autobot Spike" of the original cartoon. Sent into a coma after a Decepticon attack, Spike's mind is transferred to a robot frame his father was working on earlier, in order to let the human doctors operate on his body safely. Toss in references to the original Frankenstein, the fact that the body is a mishmash of parts, and a little bit of Con trickery... He eventually recovered, though.
However, Daniel underwent the Headmaster process and became Arcee's partner after being half-eaten by a beast Decepticon (You'd think nearly doing in The Scrappy would have made him a household name, but no.) and will presumably be stuck in that exosuit forever.Poor guy.
The Mid-Season Upgrade of Hot Shot, Red Alert, and Scattorshot from Transformers Cybertron also counts. They were dying, grievously injured by Megatron's newly-unlocked Death Machine Gun. The source of this transformation? Divine intervention by a semi-conscious Primus.
Tom from Toonami underwent a change when the Absolution was overrun with an alien blob and Tom 1.0 was swallowed up by it.
This was Sir Charles Hedgehog's motivation for inventing the Roboticizer in Sonic Sat AM. He abandoned the project when it turned out it would disable the independent will of someone subjected entirely to it. Unfortunately, the Fallen Hero war minister with plans for world domination stole the plans.
Argus: "What has happened? I have become a Robotix! NOOOOOOOOO!!!
In Centurions, Mad Scientist Doc Terror transforms street thug Hacker into a cyborg, then tells him that there's no way to change him back. Hacker's reaction is a temper tantrum that leaves Terror with life-threatening injuries, so Terror has to become a cyborg himself to survive. It would be a case of Hoist by His Own Petard, except that Terror likes his new form.
The Adventure Time episode "Betty" ends with Betty defeating Bellanoche and restoring the Crown's magic, keeping Simon alive but turning him back into Ice King.