History Main / DeadlyUpgrade

* In one mission of ''VideoGame/AssassinsCreedBrotherhood'' you get to use [[spoiler:the Apple of Eden. Any one within a certain distance goes crazy and starts fighting each other. Anyone in an even closer distance automatically dies. Every time it is used time slows down and your health gradually goes down. And you can't use any of your other weapons]].
** ''Revelation'' averts this completely. We find out Altair had the same ability but none of the drawbacks. Apparently he was a major badass for a reason.

* In ''VideoGame/{{BioShock|1}}'', the first Plasmid power you receive causes Jack to temporarily go mad and black out. Habitual plasmid use [[InformedFlaw supposedly]] causes disfigurement and eventually permanent insanity (hence all the insane splicer enemies you fight), but [[GameplayAndStorySegregation that never seems to happen to the player]] no matter how much you splice, [[spoiler:but that may be because of the many changes Fontaine and his allies made to you when you were created]].
** If you get the good ending, [[spoiler:the Plasmid exposure has clearly taken a toll on Jack, as seen when he's in the hospital with the grown-up Little Sisters he saved, his arm withered and shaking uncontrollably, as his "daughters" console him as he passes]].

* ''VideoGame/Persona3'' has this in spades. First, many Personas learn physical attack moves, but using them drains up to a fifth of the character's HP. [[spoiler:Also, Jin, Takaya, and Chidori were artificially given Personas, which will kill them if not controlled by drugs... [[SadisticChoice and the drugs' side effects include a vastly shortened lifespan]].]]
** Not only that, [[spoiler:the last move that the Main Character uses to seal away the final boss [[HeroicSacrifice costs him or her their life]]]].

* Anabolic steroids are well known for their ability to make us stronger, etc. The downside is that there are a HUGE amount of side effects, not the least of which are heart problems, cancers, "[[UnstoppableRage roid rages]]," [[ArsonMurderAndJayWalking and man-boobs]].
** ''Sometimes'' TruthInTelevision. Not all anabolic steroids and analogues are that dangerous when taken in controlled amounts to help with recovery after surgery (assuming they're pure, and illegally-obtained drugs often aren't). Others are suffering in liquid form, inviting the physiological side affects mentioned above and others, as well as significantly increasing the risk of manifestation of psychological disorders in those with pre-existing conditions.
* The body uses another steroid, cortisone, to reduce inflammation and pain, which it does by suppressing the immune system. It is primarily released during periods of stress, which accounts for consequent illnesses. And any pain inhibitor in general is risky, as pain normally prevents someone from causing injury to themselves.
** This is likely the cause of what most students experience in the form of the post-finals flu.
** Synthetic forms of cortisone, including asthma inhalers and cortisol, are used to treat a variety of diseases and symptoms, allowing those with conditions to live mostly normal lives...except for the increased risk of sickness.

* In short, most of the above substances work a bit like taking out a loan from a loan shark. It gets you what you need, when you desperately need it, but the terms of repayment are ''absolutely awful''.
%%* Chechnya was this when it became an independent nation back in 1991. This caused Russia to have a full scale war that killed a lot of people against the country and annex it as a republic of Russia.

[[folder:Film — Live-Action]]

** In 90's films, [[Characters/{{Godzilla}} the King of Monsters]] can fire a much stronger version of his blue atomic beam that is red and has lightning spiral around it if he absorbs enough energy. The down side is if he absorbs too much power he will turn into a meltdown mode that will cause a SuperPowerMeltdown that can burn up the atmosphere and kill all life. In ''Film/GodzillaVsDestoroyah'', he does end up going into meltdown mode. It's only by his son Godzilla Junior does the Earth survive: [[spoiler: when Burning Godzilla finally has a total meltdown, Junior is forced to abosrb the excess radiation, maturing into a new Godzilla.]]

* In David Weber's ''Literature/EmpireFromTheAshes'' series, the Earth defense forces give the planet itself one of these — a core tap (essentially a hyperspace funnel that produces ludicrous amounts of power but is highly unstable) is placed in Antarctica to power the planetary shield in advance of an invasion attempt. (And as some idea of just how nasty one of those is, a microsecond hiccup in power would lead to the core tap exploding and flattening "fifty-three percent of the landmass of the continent, tsunamis, sea level rise and the direct deaths of 6.5 million people" with indirect deaths impossible to calculate. That's half of Antarctica, a continent bigger than the US, through three kilometers of ice.) The Imperials who worked with core taps before practically faint at the idea of putting one on a planet — they aren't even safe to use in atmosphere, and it's visible in operation as a two-hundred-kilometer torrent of lightning that is probably harmful to the Earth even when working perfectly.

[[folder:Web Original]]
* In ''WebAnimation/RedVsBlue'', The Red's Warthog get's a literal one; It gains a powerful and potent EMP cannon capable of disabling any electronic equipment it hits with a single blast. The downside is that, since the car itself is electronic; every time they fire it, the engine stalls. Simons even pointed out the downside before they upgraded.
[[/folder]]

* ''WesternAnimation/AvatarTheLastAirbender'' has this with the Avatar state. It's a SuperMode that gives the Avatar the combined skills of all the previous Avatars, making him/her nearly invincible. Downsides are that it's hard to control without training (very bad since it turns the Avatar into a PersonOfMassDestruction), and if the Avatar dies in the Avatar state, then the Avatar's cycle of rebirth will end and the Avatar will cease to exist.
** In ''WesternAnimation/TheLegendOfKorra'', it is revealed that Aang had used the Avatar state so much between his 100 years in the iceberg and his adventures afterwards his lifeforce was drained and he died at the biological age of 66(for reference, one of Aang's close friends from before his icebath was in fighting shape at 112 and the last avatar to have a natural death died at ''230'').
* WesternAnimation/DannyPhantom uses the ecto-skeleton in Reign Storm to defeat [[NamesToRunAwayFromReallyFast Pariah Dark]], but at the cost of 95% of his life energy. He gets saved just before burning through the last of his energy by [[VillainousRescue Vlad Plasmius and every other ghostly opponent he ever had]].
* On ''WesternAnimation/JusticeLeague'', The Flash goes really, really, ''[[LudicrousSpeed really]]'' fast, and ends up nearly pulled into another dimension, communing with a quasi-mystical "[[TheLifestream speed force]]" [[MythologyGag that was the source of his power in the comic]].
* One episode of the ''WesternAnimation/MenInBlack'' cartoon had Agent Jay accidentally use an intelligence-improving device that would eventually [[YourHeadAsplode cause his head to explode]]. After using his new brain (and the RippleEffectProofMemory that comes with it) to deal with a time-traveling villain who was erasing the founding members of the Men In Black from history, Jay managed to fix it by hijacking the baddie's time machine and [[TemporalParadox preventing it from happening in the first place]].

* [[ShapeShifter Beast Boy]] from ''WesternAnimation/TeenTitans'' [[InvoluntaryShapeshifting transforms involuntarily]] into The Beast in the episode "The Beast", which he from then on is able to become at will. Said beast is incapable of higher thinking and liable to attack the other Titans, but possesses strength beyond that of his teammates and SuperSpeed.

* Rion, the protagonist of ''VideoGame/{{Galerians}}'' is a natural psychic, but he needs drugs to enhance his powers for actual use. In addition, his power steadily increases over time, with a literal bar on screen showing how much the enhancement drugs are affecting him. If the bar gets full, he enters full on PowerMeltdown: he can only limp along, occasionally suffers from seizures, and ''anyone that gets too close has [[YourHeadAsplode their head explode violently]]''. It also constantly drains his health, and if he can't take a power suppressing antidote, he'll become a OneHitPointWonder.

** The Seer takes the cake when she takes the [[FoetusTerrible unborn Source's heir]] into her womb an starts channelling its powers: yes, she does become the most powerful Demon ever seen up until that point (and possibly past that, too), but the powers prove so overwhelming she ultimately explodes, taking the entire demonic council ''and'' the unborn Source with her.

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* ''VideoGame/CommandAndConquerTiberiumWars: Kane's Wrath'' has something like this. The Steel Talon subfaction has two of these. The first is the Railgun Accelerator support power. It increases the rate of fire of a unit that has a railgun, but they take damage when it's first cast on them. Not too big of an issue because the Steel Talons can easily repair their vehicles. The second is the Adaptive Armor support power. It makes a vehicle more durable and grants it immunity to EMP weapons (very good for an epic unit because EMP weapons are of the main counters to them), but lowers their rate of fire. This can be countered with the Railgun Accelerator if the unit uses railguns. One common strategy is to draw enemy fire to a railgun-equipped unit and then use both powers on the same unit.
* ''VideoGame/BattleClash'' and ''Metal Combat: Falcon's Revenge'' have a power-up called the V-System, which increases your offensive ability and always keeps your opponent centered within your sights. In order to power this, however, your mech's energy gauge is continuously drained until you reach critical.
* It's not quite ''deadly'', but the Mega Mushroom in ''VideoGame/NewSuperMarioBros'' has the side effect of returning you to Super Mario form when its period of invincible AttackOfThe50FootWhatever wears off. Thus, if you picked it up as Fire or Blue Shell Mario, it has the net effect of stripping Mario of one of his maximum three HitPoints.
* In the web-only game ''VideoGame/{{KOLM}}'', the final upgrade you receive [[spoiler:causes a nuclear meltdown that destroys your entire home, the only place you ever see in-game. You, however, can survive]].
* In ''VideoGame/StreetFighterXTekken'', this is how Pandora works in gameplay: by sacrificing the character that you are currently using, your standby character gets a massive boost in attack power. If you can't defeat your opponent within ten seconds of activating Pandora, however, you lose automatically.
* In ''VideoGame/{{BioShock|1}}'', the first Plasmid power you receive causes Jack to temporarily go mad and black out. Habitual plasmid use [[InformedFlaw supposedly]] causes disfigurement and eventually permanent insanity (hence all the insane splicer enemies you fight), but [[GameplayAndStorySegregation that never seems to happen to the player]] no matter how much you splice, [[spoiler: but that may be because of the many changes Fontaine and his allies made to you when you were created.]]
** If you get the good ending, [[spoiler:the Plasmid exposure has clearly taken a toll on Jack, as seen when he's in the hospital with the grown-up Little Sisters he saved, his arm withered and shaking uncontrollably, as his "daughters" console him as he passes.]]
* In one mission of ''VideoGame/AssassinsCreedBrotherhood'' you get to use [[spoiler:the Apple of Eden. Any one within a certain distance goes crazy and starts fighting each other. Anyone in an even closer distance automatically dies. Every time it is used time slows down and your health gradually goes down. And you can't use any of your other weapons.]]
** ''Revelation'' averts this completely. We find out Altair had the same ability but none of the drawbacks. Apparently he was a major badass for a reason.
* ''VideoGame/Persona3'' has this in spades. First, many Personas learn physical attack moves, but using them drains up to a fifth of the character's HP. [[spoiler: Also, Jin, Takaya, and Chidori were artificially given Personas, which will kill them if not controlled by drugs... [[SadisticChoice and the drugs' side effects include a vastly shortened lifespan.]]]]
** [[spoiler: Not only that, the last move that the Main Character uses to seal away the final boss [[HeroicSacrifice costs him or her their life.]]]]
* ''Wolverine'' for the UsefulNotes/NintendoEntertainmentSystem makes WolverineClaws work this way. Once Wolverine unsheaths his claws, they replace the icon of his face and make his attacks hit harder while draining his life bar.
* In ''[[VideoGame/AsurasWrath Asura's Wrath]]'', the main character at one point enters his [[spoiler: Berserker Form]], an incredibly powerful form capable of [[spoiler: shooting down an entire armada]], but at a cost - after Asura is struck directly by [[WaveMotionGun the Brahmastra]], he enters his [[spoiler: Wrath Form]]. This scorches his body black with the fires of his own rage and it's stated that Asura's attacks do more damage to himself than his opponent when in this state.
* ''VideoGame/KillerInstinct'' has this mixed with GhostInTheMachine and UnwillingRoboticisation on Eagle. [[spoiler:After ratting [=UltraTech=] out upon winning, the company turns him into a machine, Fulgore. Unfortunately, Eagle inverts the CyberneticsEatYourSoul trope by the 2013 remake, resulting in this.]]
* ''VideoGame/SuikodenV'' introduces Raging Nostrum, a very dangerous drug developed by assassin network Nether Gate. Those who ingest the drug go into a violent rage, with greatly-increased strength... and then die shortly afterward.
* Sol Badguy from ''VideoGame/GuiltyGear'' has a special called Dragon Install where he gains speed, power and extra abilities. If it reaches its time limit in the game, Sol gets temporarily weakened and the opponent will have an opportunity to attack. In the main story this is actually Sol's true form. His PowerLimiter is the only thing keeping his human appearance and sanity although recently it begun to lose its effectiveness.
* Rion, the protagonist of ''VideoGame/{{Galerians}}'' is a natural psychic, but he needs drugs to enhance his powers for actual use. In addition, his power steadily increases over time, with a literal bar on screen showing how much the enhancement drugs are affecting him. If the bar gets full, he enters full on PowerMeltdown: he can only limp along, occasionally suffers from seizures, and ''anyone that gets too close has [[YourHeadAsplode their head explode violently]]''. It also constantly drains his health, and if he can't take a power suppressing antidote, he'll become a OneHitPointWonder.
* The [[http://www.hearthhead.com/card=846/power-overwhelming Power Overwhelming]] card in ''VideoGame/{{Hearthstone|HeroesOfWarcraft}}'' gives a minion +4 attack and +4 health until the end of the turn, which is a fair amount. At the end of the turn, said minion dies. Horribly.

* Hala the Accuser, the BigBad of ''VideoGame/GuardiansOfTheGalaxyTheTelltaleSeries'', wants to use the [[MacGuffin Eternity Forge]] to resurrect the Kree Empire and her dead son, Bal'Dinn. If Quill destroys it at the end of Episode 3, she absorbs it powers while trying to bring Bal'Dinn back to life and [[YourSoulIsMine gains the ability to steal people's souls.]] And if she doesn't keep doing it, she'll die.
* As ''VideoGame/DeusExInvisibleWar'' shows, despite giving him incredible power, [[spoiler: JC Denton's fusion with Helios]] was unstable, forcing him to go into cryogenic storage, while his allies tried to find a way to help him.
* ''VideoGame/GranblueFantasy'' has Geisenborger's "I'll Bet My Soul" skill, which gives him total debuff immunity and the ability to survive all lethal attacks while it's active. The duration of this can be extended by other characters buffing him, but the moment it expires, Geisenborger is knocked out.

* Near the end of the Nailbat story in ''Webcomic/AntiBunny'' Nailbat [[spoiler:begins trading off the last of his lifespan for enhanced physical abilities, and in the climax flight.]]
* ''Webcomic/ElGoonishShive'': Nanase's [[http://www.egscomics.com/?date=2009-10-03 Angel spell]] very nearly became this because it allowed her to keep using magic well past her natural limit. The first time she cast it, she needed to be hospitalized, and although she eventually made a full recovery, her magic was completely burnt out for months.
* ''Webcomic/ProblemSleuth'' gained wings, glowing armor, superpowered weapons/writing implements, and access to insanely potent attacks upon using [[LimitBreak Sepulchritude]], however, once his Ink of Squid Pro Quo (which powers Sepulchritude) ran dry, he was left helpless, nearly paralyzed and at the [[GoIntoTheLight brink of death]].
* In the webcomic ''Webcomic/{{Mindmistress}}'', the title character uses a piece of AppliedPhlebotinum that grants her Braniac-level intelligence. But if she leaves it active for too long, it will leave her with brain cancer, if not killing her outright.
** Similarly, Dauntless, a super-hero imbued by her, must detransform periodically or his enhanced nervous system will cause him to overload on sensory input.

-->'''[[spoiler:Zola]]''': Did you just try to poison me?! AHA!HA!HA!HA! As if that could stop me now!\\
'''Violetta''': ''*tsk*'' I know that. That wasn't poison. That was more Movit 11. Now all I have to do is watch you combust.

* In ''WesternAnimation/TransformersAnimated'', [[spoiler:Sari, after the RoboticReveal, uses her Key to upgrade herself and try to fight the asteroid monsters. As soon as the fight is over, though, she loses control of her body and starts destroying everything around her, despite her best efforts to stop, including accidentally stabbing Bumblebee when he gets too close and nearly offlining him.]]
* ''WesternAnimation/AvatarTheLastAirbender'' has this with the Avatar state. It's a SuperMode that gives the Avatar the combined skills of all the previous Avatars, making him/her nearly invincible. Downsides are that it's hard to control without training (very bad since it turns the Avatar into a PersonOfMassDestruction), and if the Avatar dies in the Avatar state, then the Avatar's cycle of rebirth will end and the Avatar will cease to exist.
* In ''WesternAnimation/TheLegendOfKorra'' it is revealed that Aang had used the avatar state so much between his 100 years in the iceberg and his adventures afterwards his lifeforce was drained and he died at the biological age of 66(for reference, one of Aang's close friends from before his icebath was in fighting shape at 112 and the last avatar to have a natural death died at ''230'').
* [[ShapeShifter Beast Boy]] from ''WesternAnimation/TeenTitans'' [[InvoluntaryShapeshifting transforms involuntarily]] into The Beast in the episode "The Beast", which he from then on is able to become at will. Said beast is incapable of higher thinking and liable to attack the other Titans, but possesses strength beyond that of his teammates and SuperSpeed.
* WesternAnimation/DannyPhantom uses the ecto-skeleton in Reign Storm to defeat [[NamesToRunAwayFromReallyFast Pariah Dark]], but at the cost of 95% of his life energy. He gets saved just before burning through the last of his energy by [[VillainousRescue Vlad Plasmius and every other ghostly opponent he ever had.]]
* ''WesternAnimation/{{Motorcity}}'': Kane has his employees invent a chip for his soldiers that makes them fearless, despite his scientists warning him it could be unstable. The cowardly Chuck finds this chip on one of the soldiers and takes it for himself. This does allow him to become more confident and stronger, but also causes him to rage out, including against Mike, his best friend. [[spoiler:Mike convinces him to remove the chip.]]

%% Image removed per Image Pickin' thread: https://tvtropes.org/pmwiki/posts.php?discussion=1637798759041234700
%% Please start a new thread if you'd like to discuss a new image.

!!Example subpages

* In ''ComicBook/XMen'' related comics (her first appearance was in ''ComicBook/XFactor'') "Infectia" was a woman whose whole power ''was this trope.'' Specifically, she could mutate other people into having superpowers, but then they died within 24 hours.

* In a ''ComicBook/SpiderMan'' arc, the Vulture was dying of cancer; feeling there was no need to worry about safety anymore, he set his flight harness to max levels that he never dared set them to before, making himself far stronger and faster than he ever was. (He almost ''did'' kill himself in the process, and nearly took Spider-Man with him as he did. It was implied that one of the biggest reasons Spidey saved him was to make him apologize to his Aunt May, who he had threatened during his RoaringRampageOfRevenge.)

* During the post-''ComicBook/{{Convergence}}'' stories, ComicBook/{{Superman}} went through two close-calls - becoming a God after the death of Darkseid during the ComicBook/JusticeLeague storyline ''The Darkseid War'' and swimming through the Fire Pits of Apokalips then charging himself up with Kryptonite during ''ComicBook/SupermanSavageDawn''. That, combined with his DisneyDeath at the hands of the Kryptonian God Rao lead to the events of ''ComicBook/TheFinalDaysOfSuperman'', where Superman is now dying because of those changes.
* ComicBook/{{Sunspot}}'s power allows him to absorb sunlight and convert it into SuperStrength. At one point he's infected with the M-Pox sickness, which messes with his powers and puts them into overdrive. He can now absorb so much sunlight that it puts his strength on par with the {{Physical God}}s like Hercules and Thor, and quite possibly makes him the strongest mutant on Earth. The drawback is that using his power to that level [[CastFromLifespan shaves years off his life]], so normally he wears a PowerLimiter to temper his absorption rate and keep himself from burning out.
* The backstory of ''ComicBook/BeastWarsUprising'' has the Triple-Threat Master process. It’s the ultimate combination of three other upgrades (Headmasters, Targetmasters, and Powermasters) and gives the subject [[SuperSoldier nigh godlike power]]. Unfortunately, it also damages spark integrity to the point that anyone who receives the upgrade has their lifespan shaved in two. Optimus Prime and Galvatron were the only people to ever risk taking it, the latter because [[AxCrazy he was crazy enough to not care about the side effects]] and the former in order to stand a chance against him.
* Happens when the titular character of ''ComicBook/MissileMouse'' absorbs the power of the [[DoomsdayDevice Star Crusher]]. He gets abilities that would make a [[Franchise/DragonBall Super Saiyan]] stand up and take notice, but will turn into pure energy if he doesn't discharge all that pent-up power ''soon''. He almost suffers this fate, but thanks to a HeroicSecondWind, he manages to hang on just long enough to let all the energy loose. Good thing he had the BigBad's fleet as a convenient target.

* ''The Beloved Helpless'': see the ''Manga/SoulEater'' entry above for [[TheCorruption Black Blood]] physics in this world. At the end of the fic, [[spoiler: Soul makes a deal with the Little Demon]] to use the Black Blood to save [[spoiler: Maka, who was mortally wounded by an insane Dr. Stein.]] It costs him [[spoiler: his soul, and when Maka finds him again, she figures out pretty quickly that the person she's talking to is his killer.]]

* ''Fanfic/CalvinAndHobbesTheSeries'': When Calvin [[SuperheroEpisode gains superpowers]], he also is prevented from regaining his energy, meaning that if he doesn't get it fixed (which will DePower him), he'll die of exhaustion. His powers also use a lot of his energy, which just speeds up the process [[spoiler: to the point where he dies near the end of the episode, which has to be undone by Hobbes time-traveling to the past and warning Past!Calvin to not do the thing that gave him superpowers.]]
* In ''Fanfic/ImaginarySeas'', Percy requests Hephaestus to make his version of Trident Ocean Ray as powerful as possible with full knowledge that it would certainly kill him by the time he's done with it. Since fighting his father would be a SuicideMission regardless, he says that he might as well have every ounce of power he can to make it one with some chance of success.
* [[spoiler: [=ChaosGallantmon=]]] for Takato in the ''Fanfic/TamersForeverSeries''
* [[WesternAnimation/DannyPhantom Danny]] develops a SuperMode in ''Fanfic/FacingTheFutureSeries''. Unfortunately, while it does give him a massive power increase, the energy builds up too quickly and threatens to burn Danny's body out if he uses it too long.
* Shirou Emiya in ''[[https://www.fanfiction.net/s/11905736/1/Fate-Gamer-Night-SE Fate Gamer Night]]'' manages to unlock both a MadeOfIron upgrade and an outright SuperMode, each with their own drawbacks. The first is called "Die Hard" and allows Shirou to keep functioning even at zero health so long as he has stamina left but drains said stamina at a ridiculous rate. The SuperMode is a prototype of Unlimited Blade Works and functionally coats all of his bones with swords, massively boosting both Shirou's offense and defense while also completely shredding his body with every movement.

* Near the end of ''Literature/{{Worm}}'', [[spoiler:Panacea unlocks Weaver's potential and the latter's passenger starts taking control.]] Although this upgrade definitely helps [[spoiler:Weaver defeat Scion,]] it screws with her head and gradually causes her to lose all sense of reason and coordination. By the end of the fight she can't speak, can't understand speech, and can barely stand up straight. This ends when [[spoiler:Contessa puts a bullet in Weaver to destroy the passenger and surprisingly spare her life.]]
** Also, second trigger events. Basically, there is an extremely small chance that parahumans exposed to really similar circumnstances to those in which they had their trigger event will undergo another one that will strenghten, alter and deepen the level of complexity of their power. Second trigger events aren't dangerous on their own, but the psychological toll one must undergo to get one is, and generally speaking those who undergo them die in a few years.

* A supplement for the ''TabletopGame/MutantsAndMasterminds'' system includes a drawback ([[GameBreaker though how much of a drawback it really is is contested]]) called Holding Back. When triggered, the character in question gains a huge power boost, but side effects range from attracting attention from powerful enemies to going berserk on your allies to becoming comatose afterward.
* The ''Complete Mage'' supplement for the [[TabletopGame/DungeonsAndDragons 3.5th Edition of D&D]] features the spell [[ExactlyWhatItSaysOnTheTin "Transcend Mortality"]] for the [[ElementalPowers Wu Jen]]. It gives [[NighInvulnerability DR 30/epic]], [[PowerNullifier SR 21+CL]], [[ElementalRockPaperScissors resistance to all five energy types]], [[StatusEffects immunity to abilitiy damage/drain/disease/poison/death effects]], and [[SuperNotDrowningSkills negates your need to breathe]]. The catch? The spell lasts for roughly 2 minutes (depending on the mage's level), after which [[DisintegratorRay you immediately die and turn to dust]]. Said death cannot be prevented by ''any'' means.
** As with all things D&D, this can be made into a GameBreaker. The Spellguard of Silverymoon learns to cast spells on nearby others that normally only work on themselves. And Transcend Mortality can be dismissed by the caster at any time.
** Also, while DeathIsCheap by the time you can use it, only four very, ''very'' powerful spells can bring back someone who has been turned into dust. Namely:''Wish'', ''True Resurrection'', ''Contingent Resurrection'' (which is an Epic level spell), and ''Miracle''.(although you can create more epic spells to resurrect someone from such a state)
** AD&D incarnation of Leanan Sidhe (see above) -- a vampiric spirit who charms bards, inspiring, and boosting their abilities, but gradually draining hit points (permanently).

* ''TabletopGame/ChangelingTheDreaming'' used Leanan Sidhe to create a whole house of Sidhe who did just that - and a game mechanic for all fae to do the same.

* ''TabletopGame/{{Exalted}}'' has a martial art technique known as Birth of the Perfected Ego Juggernaut. Anyone (ally or enemy) struck by it gains an enormous power boost, allowing them to effortlessly succeed at nearly anything...for about ten minutes. Each minute after the effect activates, the power drops a bit, until by the tenth it's gone entirely. The catch is, at no point does the subject of the attack notice the decline. To themselves, they remain an awe-inspiring, completely unstoppable force of nature. The madness creates elaborate excuses for failures and is permanent (barring healing magic, which does nothing to stop any feeling of depression in someone no longer effortlessly flawless).
* In ''TabletopGame/TheDarkEye'', druids have a skill to transform all their life points, endurance points and several attributes into magic ability and cast spells without restriction for an hour. Once started, the process cannot be stopped, and the caster ends as [[DeaderThanDead a pile of ashes.]]

* The eponymous mark in ''VideoGame/MarkOfTheNinja'' is made of a plant toxin that, when applied to the skin, gives a variety of sense-enhancing powers to anyone with the tattoo but eventually drives them to murderous insanity. As such, people who accept the mark take an oath to commit suicide once their mission is over.

* ''VideoGame/DungeonFighterOnline'':
** Berserkers get the Frenzy skill, which more or less makes them BloodyMurder Personified (blood weapons, Blood boost), but drains health over time. Though use of HP regeneration [[BribingYourWayToVictory Avatar items]] can slow the process.
** The Berserker skill, Thirst, qualifies as well. At a cost of 12 percent of the berserker's max HP, bleeding damage is significantly increased, certain skills do more damage, and the berserker can absorb more HP from his slain enemies. This, combined with Frenzy, makes the berserker's HP unstable as it's constantly shifting upward or downward.
* ''VideoGame/FrontMission'' has a fair bit of these as shown in the video games and other media.
** The Bioneural Device is a unique interfacing device that lets pilots control their machines with human-like precision, often allowing them to exceed said machine's limitations in performance. However, pilots must undergo special augmentation surgeries which don't always quite turn out for the best. Puppet Soldier users have greater control over their machine's motions, but their minds can be taken over and have their actions remotely controlled by a "puppet master". Doll Eye users have 360-degree vision and can control nearby electronic systems to some extent, but are subject to blindness and extreme eye pain if they are hit with flash bang grenades. S-Type users can control their machines as if they were their own bodies and can do incredible feats on the battlefield because of it, but they are physically affected by EMP attacks, their organ sensitivity is so high that even minor damage can be fatal, and they can suffer from massive memory loss. Puppet Soldiers show up in ''2089'' and ''2089-II''. Doll Eyes appear in ''2089-II'' and the ''Dog Life & Dog Style'' manga. Finally, S-Types can be seen in ''2089'', ''2089-II'', ''1st'', ''Online'', ''5'', and ''Dog Life & Dog Style''.
** While it isn't exactly like the other Bioneural Devices, the B-Type also counts in a way. The B-Type is a device which is powered by a human brain and when put inside a machine, allows for autonomous control of it. Machines can attack targets or evade enemy fire without needing input from its pilot. The downside? B-Type devices are very unstable and have led to the deaths of pilots using machines with them, [[spoiler: such as Laurent Connely when his B-Type-powered wanzer stopped moving and he was shot to death by nearby OCU units.]] Appears in ''1st'' and ''Online''.
** The Imaginary Numbers in ''3'' also count. The Imaginary Numbers are a group of genetically-engineered humans with above-average intellect and exceptional abilities in combat, such as their reaction time and tactical knowledge. The Imaginary Numbers, while deemed superior to their predecessor the Real Numbers, were far less stable mentally and thus vulnerable to becoming insane under certain conditions.
* ''[[VideoGame/GuardianHeroes Advance Guardian Heroes]]'' combines this trope with DealWithTheDevil: if you run out of HP, you're given the option of being granted an even more powerful body for a limited time. Accept, and you will be given an invincible body for six minutes. Once the time limit expires, though, your soul will be taken, and you will receive a GameOver, with your progress being set back to before you accepted the offer.
* ''VideoGame/MassEffect2'' shows this as an ability of the Collectors, a curious race who have more implants than internal organs per member. As [[BigBad Harbinger]] [[MoreThanMindControl takes direct control of a mook,]] these implants go into overdrive, and the individual Collector gains a massive damage buff, biotic abilities, and an [[VolcanicVeins evil-look]][[GlowingEyesOfDoom ing glow.]] However, as they take more and more damage, their implants are forced to increase in power, until they can take no more, and the Collector's body is disintegrated. [[WeHaveReserves Not like Harbinger cares, though.]]

*** The Dominus Union. It will kill all enemies on-screen [[spoiler:at the expense of consuming your soul and thus killing you.]]This later becomes [[spoiler:an important plot point.]]
* The dragon transformation in ''VideoGame/BreathOfFireDragonQuarter'' results in rapid accumulation of points on the D-Counter, which constantly increases at a much slower rate, cannot be lowered by any means, and results in a NonstandardGameOver when it hits 100%, strongly discouraging you from using it at all.
* ''VideoGame/BreathOfFireIII'' has the Kaiser dragon form. It's Ryu's most powerful dragon form, but the first version you get you can't control Ryu when he uses it. You can, however, get a controllable version.
* ''VideoGame/EarthBound1994'' has the party [[spoiler:become robots in order to time travel, because time travel does not work on organic matter. No guarantee exists that the characters' souls will find their way back from the robots afterward, though naturally they do.]]
* In ''VideoGame/SuperLesbianAnimalRPG'' [[spoiler:Paula]] is granted powerful fire magic by [[spoiler:The Godess of Magic herself, Queen Verena]] Allowing her to cast powerful Hellfire attacks in battle. She was infused with so much mana so fast however that her body was not able to handle it, and she collapses halfway through battle. If Melody hadn't been able to use a ManaDrain spell on her in time, she could have died from a mana overdose.
* In ''VideoGame/FinalFantasyIVTheAfterYears'', Ceodore learns an ability called Awaken. When he uses the ability, his stats increase dramatically, but a few turns later, he drops into single-digit hit points, meaning one hit from anything and he dies. This is definitely deadly if a battle is still going on.
* In ''VideoGame/FinalFantasyXII'', Judge Bergan gets powered up with nethicite. Not by holding a stone of the stuff, but by ''getting it set in his bones''. Thanks to nethicite being as volatile as it is, this leads to [[spoiler:it ''exploding'' after his boss fight, killing him instantly. [[GoryDiscretionShot The player is spared the details]], but Balthier (who took a look under Bergan's armor) is not.]]
* ''VideoGame/FinalFantasyXIV'' has two of the Tank jobs' invulnerability skills, which grants them immunity to most forms of damage, but at a cost:
** The Dark Knight has the "Living Dead" skill: if the Dark Knight's HP drops to 0 while the skill is active, they will enter into a "Walking Dead" state that renders them invulnerable for ten seconds. If their HP is not fully recovered before the invulnerability ends, however, they will drop dead on the spot.
** The Gunbreaker has "Superbolide", which grants them instant invincibility for eight seconds, but at the cost of reducing their HPTo1, leaving them in a highly vulnerable state if their HP is not recovered before the invincibility ends.
* In ''VideoGame/FinalFantasyXV'', only the Royal bloodline can wear and use the Ring of The Lucii, while most commoners are instantly killed if they dare to wear it. Certain champions of the kingdom can be given special permission by kings and queens past to wear the ring properly and fight like a royal, but at the cost of permanent damage to their health that can end in death, as demonstrated with Ravus, who had to replace his left arm with a magitek prosthesis [[spoiler:as well as Ignis, as shown in the DLC "Episode Ignis", who went blind and suffered facial scarring]].
* In the ''Heaven's Feel'' route of the ''VisualNovel/FateStayNight'' {{V|isualNovel}}N, [[spoiler:Shirou gets Archer's arm transplanted onto him after his own is lost and Archer is dealt a fatal wound.]] It is wrapped in a cloth that seals its power, but even if left like this, it would kill him from power overload within ten years unless he [[spoiler:cut it off or became a good enough mage to seal it himself.]] Just ''loosening'' the cloth causes significant memory loss. Taking it off completely is a guaranteed death sentence, with rapid destruction of mind and body on top of that with every use. [[spoiler:He still manages to overcome Black Berserker, Saber Alter (with the help of Rider; he technically beats Saber Alter alone in a Bad End, but it requires [[BrokeYourArmPunchingOutCthulhu burning out his mind]] and she's still alive and would regenerate from the damage), Kotomine (by virtue of [[VictoryByEndurance outlasting his foe's own remaining lifespan]]), and (in the "Normal End") the corrupted Grail before his mind dies.]]
* In ''Franchise/DotHack'', Kite has Data Drain, which weakens enemies to the point where they can be taken out with a single hit. But using it can result in level and stat reductions or an instant game over. He gets an upgrade that allows him to use it on multiple targets and yet another that increases the chance of getting a rare item, but both increase the likelihood of negative effects occurring.
* The Mercenaries of ''VideoGame/TeamFortress2'' have all underwent an entire heart transplant that replaced their normal hearts with that of the "Mega Baboon" and possibly even the "Loch Ness Hamster" to be able to be used for an ÜberCharge. However, as [[MadScientist The Medic]] has shown, normal hearts tend to explode when exposed to the beam that grants the charge, and he prefers to perform the operation while his patients are still awake. Making the threat of bleeding out or losing vital organs to the madman seem very possible despite the healing devices he has set up.
* In ''VideoGame/{{Haze}}'', you have access to a super-drug called ''Nectar'' which gives you enhanced speed, accuracy, and grenade range, but overdosing could result in losing control of your character or even death. And that doesn't count the narrative effects: low exposure to ''Nectar'' makes the user susceptible to consciousness alteration, which is used by the corporation that creates it to prevent their soldiers from [[spoiler: seeing dead bodies, and by extension seeing the results of their combat actions.]]
* In ''VideoGame/{{Crimsonland}}'' you can activate the ''Death Clock'' perk which gives you 30-second invincibility..after which you die.
* ''VideoGame/MetroidPrime3Corruption'': A central point. Samus gets a powerful "Phazon Enhancement Device" added to her suit that allows her to transform into a hyperactive killing machine, but over-use of it will cause her to become 'corrupted' and [[NonstandardGameOver end the game.]] Using the PED also explains why the SpacePirates' experiments with Phazon frequently caused UnstoppableRage: Firing indiscriminately is the easiest way to get rid of excess Phazon, preventing an overdose. And even if you don't overuse it, it'll probably kill you anyway - witness the PED-equipped Marine with the suspiciously shaky hands in the Preview Channel video, to say nothing of [[spoiler:the other three hunters, who apparently go over to the Dark Side right out of the gate, and AU 242's warning to Samus on Bryyo:]]
--->[[spoiler:"We have discovered that the unique Phazon in your body, once activated, will eventually overreact, resulting in terminal corruption. In providing you with the PED, we have inadvertently placed you in grave danger. (pause) We are sorry."]]
* In ''VideoGame/LuminousArc3'' [[spoiler:Refi]] receives one that greatly powers him up, at the expense of losing his humanity every time he uses it, starting with his senses. Surprisingly enough, it is strongly impled that he [[spoiler:has not regained the senses he lost by the end of the game.]]
* Used in ''VideoGame/KingdomHeartsII'' with Anti-Form. Engaging a Drive form (other than Final Form) has a chance of instead turning into Sora into something akin to TheHeartless (suggested to be his connection to [[spoiler:when he briefly changed into one in the first game]]). Anti-Form is completely unable to gain experience, and it's completely unable to recover health. Slightly related to both, it's also the only form that Sora can't cancel partway through. It's not bad if you're just starting against a boss, and at full health. But if either recovery or experience points are in the coming, you will be affected by the downsides.
* In ''VideoGame/PrinceOfPersiaWarriorWithin'' the Prince at one stage [[spoiler:puts on the 'Mask of the Wraith', which sends him back in time and transforms him into a monstrous wraith. In this form his health slowly drains, stopping at 25% of base health (enough to take a single hit without dying, and then only certain ones) but his sand tanks refill on their own at such a fast rate that he effectively has unlimited sand.]] Under the circumstances, you need it.
* In ''VideoGame/PrinceOfPersiaTheTwoThrones'' at certain points, the Prince transforms into the Dark Prince, who is faster and stronger, but cannot use his left hand for grappling or picking up weapons, instead he has a spiked chain-whip. In addition, he slowly loses life to the darkness (unlike the above, this will be fatal eventually), which can be replenished by absorbing Sands of Time. He reverts back to the original Prince if he touches water.
* In ''VideoGame/PrinceOfPersia2: The Shadow and the Flame'', transforming into the Shadow shortens your life meter by many potions, and using the Flame [[CastFromHitPoints costs further health.]] Both are necessary to defeat the FinalBoss.

* Rampage Mode in the ''VideoGame/{{Oneechanbara}}'' series, a product of the Baneful Blood carried by most of the playable characters. Their offensive abilities are greatly increased, at the cost of taking double damage and constant health drain. There's also a Double Rampage Mode which is even more powerful and even more deadly.
* ''VideoGame/ValkyrieProfileCovenantOfThePlume'' has the titular Destiny Plume - when used on an ally, it multiplies their base stats by 10, makes them immune to status aliments and elemental damage and lets them use an extremely powerful character-specific ability TheHero learns permanently after the battle, but it [[KilledOffForReal costs them their life]] at the end of the battle. It could almost count as a HeroicSacrifice, except the choice is never theirs to make.
* At the end of ''VideoGame/IndianaJonesAndTheFateOfAtlantis''. [[spoiler:You discover an ancient Atlantean machine that transforms men into gods, and the Nazis want to reward Dr. Jones for the find by letting him be the first to use it and ascend to godhood. Whilst using it does indeed transform the user into a god-like [[EnergyBeings Energy Being,]] the resulting being never lives for more then a minute.]]
* ''VideoGame/AgeOfWonders: Shadow Magic'' has [[http://aow2.heavengames.com/aowsm/gameinfo/magicspells/life.shtml#martyr Martyr]] enchantment: it doubles one unit's HP, but this unit dies once the battle ends.

* In ''VisualNovel/{{Tsukihime}}'', even before the story starts, Shiki had the Mystic Eyes of Death Perception activate, greatly supplementing his killing power. Obviously. Of course, it burns his brain out and he'll die in ten years or so but... Also when he overtaxes even ''that'' in order to see [[spoiler:Satsuki's polluted blood in his veins, open his brain up to be able to comprehend the death of things that aren't even alive, and worst of all, use his eyes as X ray eyes ''while'' looking for poison to kill in Kohaku's blood. The last one sends him temporarily blind as well as surely cutting his life back a few more years.]]
* If the Mimigas in ''VideoGame/CaveStory'' consume the red flowers, they transform into giant, hulking, quite literal {{Killer Rabbit}}s. Unfortunately, this transformation cannot be reversed, it drives them insane with bloodlust, and it kills them after a short time. The Mimigas did once eat the flowers deliberately in order to drive off a great threat, knowing full well that those who did so were sacrificing themselves regardless of whether they won or not.
* Ragna the Bloodedge from ''VideoGame/BlazBlue'' has his Azure Grimoire (or Blazblue to go with the title drop). His right arm gets chopped off in his backstory and is replaced with the remains of an EldritchAbomination. Said arm makes him a OneManArmy strong enough to be considered to be the most wanted man in the world, however using it causes the arm to assimilate and turn him into said EldritchAbomination. Naturally Ragna is extremely reluctant to use it unless he's pushed far enough. In gameplay, this translates to his "Blood Kain" LimitBreak, which augments his damage output and combo potential but drains his health bar with each passing second.

* ''Franchise/TheElderScrolls'':
** Becoming a [[OurLichesAreDifferent Lich]] is a very literal case of the trope. Mortal sorcerers, often {{necromancer}}s, undergo a ritual that turns them undead while greatly increasing their magical power and also gives them [[ImmortalitySeeker the undead form of immortality]]. This is common among the senior members of the [[TheOrder Order of the Black Worm]], a reclusive MagicalSociety who mainly study TheDarkArts, following in the footsteps of their leader (and first ever Lich), Mannimarco, the King/God of Worms.
** As most prominently seen in ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'', [[BarbarianTribe Reachmen]] warriors may choose to become "Briarhearts." A [[HarpingOnAboutHarpies Hagraven]] will remove the warrior's heart and replace it with a Briar Heart, a magical organic object which looks something like a pine cone. The Briarhearts receive a massive power upgrade at the cost of free will and thought. They also pick up the WeaksauceWeakness that if the Briar Heart is stolen (say, by a skilled pickpocket) or damaged (say, by a skilled archer), they will fall dead instantly.

* ''VideoGame/EarthBound'' has the party [[spoiler:become robots in order to time travel, because time travel does not work on organic matter. No guarantee exists that the characters' souls will find their way back from the robots afterward, though naturally they do.]]

* Adrenaline. The body's own flight-or-fight system normally doesn't pump enough of it to harm you. However, combine it with certain heart conditions and you will not survive. Also, ''external'' doses of adrenaline are not so limited and can cause your heart rate to skyrocket, or even a myocardial infarction (in layman's terms, a heart attack). And this isn't even getting into adrenal disorders like Adrenaline Overload (as some doctors call it), which is basically the flight-or-fight system activating randomly and not turning off for a while.

** The limiters can be turned off manually, without the need for an adrenaline rush, but it requires specific training to do so. Thankfully, the trainingthis trooper received came with a skill for understanding the body's risk for damage internally as a means of knowing when to limit activity. An example is this trooper when arm wrestling his one friend who had significantly higher strength. As the friend began to push down, this trooper willed himself to match his strength, but turned it off as he actually felt his ulna starting to flex and bend rather sharply and was able to stop in time so as not to have his arm snap like a twig. In terms of general exertion, the most this troper faced was elevating his heart rate to 240 for about 90 seconds, rendering him temporarily blind and unable to stand until his heart calmed down. Actual adrenaline rushes had a reduced effect (given he was already overclocking his body).

* The backstory of ''ComicBook/BeastWarsUprising'' has the Triple-Threat Master process. It’s the ultimate combination of three other upgrades (Headmasters, Targetmasters, and Powermasters) and gives the subject [[SuperSoldier nigh godlike power]]. Unfortunately, it also damages spark integrity to the point that anyone who receives the upgrade has their lifespan pretty much shaved in two. Optimus Prime and Galvatron were the only people to ever risk taking it, the latter because [[AxCrazy he was crazy enough to not care about the side effects]] and the former in order to stand a chance against him.

* In ''VideoGame/CastlevaniaPortraitOfRuin'', it is revealed that the Vampire Killer whip drains the life force of any non-Belmont who uses its true power. Jonathan Morris is warned against relying on it too much. Luckily for him, though, it takes longer than covered in one game to kill you...[[spoiler:but his father used it too often, which ultimately killed him.]]
** Also, in ''[[VideoGame/CastlevaniaOrderOfEcclesia Order of Ecclesia]]'', you can get an item called the Death Ring. It boosts all your stats by a considerable amount...at the cost of you effectively becoming a OneHitPointWonder.
*** There are also the Dominus Glyphs. Using one deals tremendous damage, and at the same time takes off a sixth of your HP.
*** Not to mention using the Dominus Union. It will kill all enemies on-screen [[spoiler:at the expense of consuming your soul and thus killing you.]]This later becomes [[spoiler:an important plot point.]]

** Similar deal in ''VideoGame/BreathOfFireIII'' with the Kaiser dragon form. It's Ryu's most powerful dragon form, but the first version you get you can't control Ryu when he uses it. You can, however, get a controllable version.

*** Not to metion using the Dominus Union. It will kill all enemies on-screen [[spoiler:at the expense of consuming your soul and thus killing you.]]This later becomes [[spoiler:an important plot point.]]

** ''Series/KamenRiderBuild'':

** Geiz's Revive form in Series/KamenRiderZiO works by ''contracting and expanding time itself'' to provide his super strength and speed, which puts such a huge strain on his body he comes out ''bleeding'' from using it. Woz also mentioned that continued use of its powers would eventually kill Geiz. [[AbortedArc This drawback was dropped]] later on, with WordOfGod lampshading it as Geiz's constant use of the form instead ''[[DieOrFly physically trained and adapted his body to overcome the drawback]]''.
** ''Series/KamenRiderZeroOne'' has two examples, the first being Zero-One's [=MetalCluster=] Hopper form, which is forced on him by one of the show's villains. The form places the suit under the control of a homicidal AI with Aruto helpless to do anything but watch, and to twist the knife, it hacks the TransformationTrinket so that [=MetalCluster=] is the ''only'' form available, forcing Aruto to either fight as a berserker or not fight at all. Aruto's allies eventually craft a weapon that eliminates both drawbacks. Kamen Rider Vulcan's EleventhHourSuperpower Orthoros Vulcan is an unusual example, as while it's not especially straining to use, it's such an unstable transformation that after about a minute it causes his belt to ''explode''.

** ''Series/KamenRiderRevice'' has an unusually slow example in the Rolling Vistamp, which allows Ikki and his inner demon Vice to combine into the powerful Jack Revice form. As a side effect, it makes Vice tangible and Ikki intangible...but Ikki still needs to eat, and Vice will still die if Ikki dies, so they have to quickly race to find a solution before they die of starvation.
** ''Series/KamenRiderGeats'' has the Boost Form Mark II. Its the fastest form Ace has, the strength it backs up, and it can turn him into a fox. In addition, unlike the regular Boost Buckle, this one does not fly away upon using the FinishingMove. But there is one flaw, the form is taxing on Ace's body and he suffers from fainting spells after every usage.
* ''Franchise/PowerRangers'' is usually LighterAndSofter than KR, so it happens rarely, but it turns up:

** And naturally, it is much more likely to pop up in battles with Organization XIII members, many of whom are the bosses you [[ThatOneBoss most need healing and damage resistance for]].

[[folder:Anime and Manga]]

[[/folder]]

** In ''Series/KamenRiderKabuto'', the SuperPrototype Hopper Zecters seem to come with a requirement of [[WithGreatPowerComesGreatInsanity insanity]].
** In ''Series/KamenRiderDenO'', Zeronos uses cards that consume the memories that others have of him to transform. As bad as this sounds, ''Den-O''[='s=] rules of time travel make them worse in context: the past is determined by ''what people remember'' of it. When the last memories of Zeronos are erased, he himself becomes RetGone.

*** The Sclash Driver in is said to be an improvement to the original Build Driver, but every usage makes the user more aggressive and violent than the last. For a while Sento does his best to keep Banjou from using it for this reason, but he manages to conquer it via force of will.

* Eversor Assassins in ''TabletopGame/Warhammer40000''. These drug-crazed killing monsters are called the Latin word for 'Destroyer' for a reason, enemies (or walls) don't last long when they are around. Eventually all of the genetic alterations, combat drugs, and bionics with which they are equipped overwhelm their hyperactive immune system and they overheat rather explosively. The only thing that keeps them alive between missions is that they are kept in cryogenic stasis.

* [[ShapeShifter Beast Boy]] from ''WesternAnimation/TeenTitans'' [[InvoluntaryTransformation transforms involuntarily]] into The Beast in the episode "The Beast", which he from then on is able to become at will. Said beast is incapable of higher thinking and liable to attack the other Titans, but possesses strength beyond that of his teammates and SuperSpeed.

* In ''Machinima/RedVsBlue'', The Red's Warthog get's a literal one; It gains a powerful and potent EMP cannon capable of disabling any electronic equipment it hits with a single blast. The downside is that, since the car itself is electronic; every time they fire it, the engine stalls. Simons even pointed out the downside before they upgraded.

!!Examples

* ''Franchise/DragonBall'':
** The Kaioken technique introduced in ''Anime/DragonBallZ'' [[InformedFlaw supposedly]] risked permanent damage to Goku's body whenever he used it -- especially when he overclocked it. However, thanks to MyKungFuIsStrongerThanYours, by the time he's fighting against Frieza, he can multiply it by twenty-fold with fairly limited drawbacks. [[spoiler:By ''Anime/DragonBallSuper'', Goku learns to combine Kaio-Ken X 10 with the Super Saiyan Blue form, but the first time Goku tried it, it was still a work in progress and initially only had a 10% success rate, with the other 90% spelling severe injuries or even death, and even when it does succeed, it can leave Goku unable to use his ki afterwards]].
** Super Saiyan 3 is another example. A few minutes of use drained Goku (who was dead at the time, but who was given 24 hours of life force so he could visit his family) of about 12 hours of his life force, and Gotenks, who burned out his 30-minute fusion in 5 minutes. Goku eventually manages to mostly iron out this flaw, but by the time he does, Super Saiyan 3 has become SoLastSeason.
*** Brought up once again in the Future Trunks arc of ''Anime/DragonBallSuper''. It's revealed that the Kai's Fusion earrings are [[spoiler:only permanent for Kais. For mortals, the fusion lasts 1 hour (which was the real reason they defused when absorbed by Super Buu). Super Saiyan Blue Goku and Vegeta use them to form Vegeto Blue, but the combination burns so much energy that the fusion lasts only about 5-10 minutes.]]
** Also from the Future Trunks arc. The fusion between [[spoiler:Goku Black and Zamasu]] is literally a deadly upgrade for the latter. He is immortal, but the other half is a mortal. By fusing with him it means that his body is now half-mortal, thereby making him mortal and finally killable - albeit insanely powerful and still nigh-invulnerable.
** ''Anime/DragonballGT'' reveals that by taking control of the transformation into an ape, a Saiyan can reach Super Saiyan 4, which Goku and Vegeta can maintain ''without'' exhausting themselves. However, the real problem comes when they perform a FusionDance into Gogeta against Omega Shenron, who has enough power to waste their galaxy if he wanted. Gogeta can use ''both'' Goku's and Vegeta's deadliest attacks ''[[AllYourPowersCombined as one,]]'' the first hit knocking out Omega Shenron's stolen Dragon Balls, and the second would've ''killed'' the weakened Syn Shenron...but he's too much of an idiot clown to do the job soon enough. Instead, he forgets the fusion will only last 30 minutes, and wastes precious time screwing with the dragon on ''cheap parlor tricks.''[[note]]It wasn't a goof-off waste of time. He was purposefully acting that way in order to get Shenron to use his negative karma attack so that he could reflect it and convert it into a positive karma attack, thereby dispelling the cloud surrounding the Earth. It just took too long to get that job done before "getting serious".[[/note]] When Gogeta ''does'' try to execute the final blow...[[EpicFail the fusion comes undone...]]with less than ''[[OhCrap ten]]'' minutes elapsed. And they ''[[CurbstompBattle pay]]'' for it...
* ''Manga/DGrayMan'': Every exorcist has a synchronizing rate with their empathetic weapon. If they force their Innocence to go over this rate, they can gain a power boost but their bodies break down and they suffer a HeroicRROd.
* Creator/JunjiIto wrote a horror story called ''Dying Young'' in the anthology ''Flesh-colored Horror.'' The premise involved a mysterious contagious symptom that makes girls incredibly beautiful, but eventually causes the girl to drop dead in a couple months.
* ''Manga/InuYasha'''s transformation into his [[SuperpoweredEvilSide full-demon form.]] His demonic blood devours a little more of his mind every time, so his demonic form becomes more and more uncontrollable. When he first transforms, he sounds like Inuyasha on a ''really'' bad day, but by the end of the series, his full demon form is incapable of speech and Kagome is unable to snap him out of it.
** And as an inversion, he can also transform into human form during the nights of the New Moon. What makes this a "Deadly Upgrade"? Simple; in human form, he loses all of his demonic powers, meaning he's easy prey for any of the demonic enemies he's made in his life...or, indeed, any true demon that realizes what he is, as half-demons are almost universally despised by their full-blooded kindred.
*** Furthermore, he only transforms when facing down enemies it would take him literally seconds to kill with full power. These episodes are usually both awesome and frustrating. His human form can sometimes fall into NotCompletelyUseless as well, as being a human allows him to circumvent and NoSell things that would be dangerous or otherwise lethal to anyone with demonic blood, such as the demon purifying barrier of Mt. Hakurei. He's still got all the disadvantages of being mortal, but it's saved his bacon more than once.
* Almost every extremely powerful technique in ''Manga/{{Naruto}}'' is some version of this.
** The various stages of Naruto's Jinchuriki transformation, from Versions 1 and 2, to Partial Transformation, to Tailed Beast Mode all involve the Fox's influence gradually taking over Naruto's mind, body, and soul. If he goes past the 4-Tailed form, nothing but the words of encouragement from his father and mother can save him from the Fox's wrath. This also lessens Naruto's lifespan, not that that matters when he's the descendant of a clan known for its natural longevity. [[spoiler:Naruto eventually tames Kurama and gains access to [[HourOfPower five minutes of using Kurama's maximum power.]]]]
** Naruto's upgraded Rasengan, the Rasenshuriken, is basically a magical fletchette bomb that attacks targets at a cellular level, inflicting massive and very hard-to-heal damage. Unfortunately, since it's held in the hand, [[LogicalWeakness it does this to the user as well.]] [[spoiler: Naruto removes this weakness by perfecting the technique to the point where he can throw it, getting it far enough away from himself that he isn't hit by it.]]
** Tsunade possesses a technique that allows her to instantaneously regenerate by speeding up her cell division which means it also shortens her lifespan. She is also a descendant of the Senju/Uzumaki clans, so how much this actually matters is currently unknown.
** ''Naruto'' also has Rock Lee, whose power revolves solely around the DeadlyUpgrade, in that he can open up certain chakra gates to gain large power boosts at the expense of damaging his body. The more gates he opens, the more injured he becomes, and if he were to open up all gates, he would become extremely powerful for a short time and then die.
*** Might Guy [[spoiler:uses all Eight Gates at one point, giving him strength and speed surpassing even [[SuperMode Tailed Beast Mode Naruto]] only to collapse into a pile of ash and bone fragments once all his energy reserves are used up. The end result was avoided with Naruto's HealingHands, but even his powers couldn't save Guy's leg.]]
** Choji's Three Colored Pills each give as successive boost in chakra, but burn out the user's body. The final, red pill instantly burns all the fat from his body and converts it to energy, but nearly kills him in the process. It would likely be fatal to anyone who's ''not'' as fat as he is. The pill also causes the user's cells to break down. When he takes it, he nearly dies and is only saved by intensive medical care and medicine from the Nara clan.
** Simply implanting Hashirama Senju's cells into a person's body can grant them enhanced regeneration and sometimes even the ability to use his [[GreenThumb Wood Release techniques.]] However, the cells can grow explosively if not properly controlled, transforming living flesh into a tree.
** The Mangekyo Sharingan will eventually render its user blind and result in extreme fatigue. Excessive use of Amaterasu can cause the user's eye to bleed. Sasuke was nearly rendered blind after he used it liberally in a misguided RoaringRampageOfRevenge. The only fix is to take someone else's Sharingan and implant them as your own.
*** Izanagi will grant the user a moment of NighInvulnerability, but permanently blinds the Sharingan used.
** Orochimaru's Curse Seal allows the person to use more chakra, and increases their attack power, but using it for too long will corrupt them and the seal will completely take over. Sasuke was unusually capable of controlling this [[spoiler:and the otherwise unstoppable transformation of the person from whom the Curse Seal originated. But now Sasuke seems to have lost the Curse Seal altpgether in his fight with his brother.]]
** In the fillers, Kagerou's Ephemeral Vengeance technique seemingly shortens her lifespan, [[spoiler:even though it is not what kills her.]]
** Pain ([[spoiler:Nagato]]) used the Demonic Statue to suck out the souls of Hanzo's men, which emaciated his body. Later, Pain's jutsu that destroys much of Konoha shortens his lifespan. Even just maintaining his HiveMind and using any of his jutsu wreaks havoc on his ''real'' body. According to Konan, he's in danger of dying due to overexerting himself in his battle with Naruto. [[spoiler:This might be why he follows "Madara" despite his own incredible power.]] Then he uses a jutsu to [[spoiler:DisneyDeath revive everyone he killed, and this ages him to death. He only gets to revitalize his body after death in Edo Tensei, using the Preta (Hungry Ghost) Path's powers to suck in Killer B's Version 2 chakra, reversing his transformation.]]
* People who possess the ''Manga/DeathNote'' in the anime of the same name can give up half of their remaining life span to gain the ability to discover the true name (which, [[MagicAIsMagicA by the rules,]] they need to know to kill a person) of anyone whose face they can see. An even larger downside is that if they lose their Death Note, they lose the power-- but also the half of their remaining life they sacrificed. If they find their Death Note again, they have to sacrifice half of their remaining life again to regain the power, meaning they'd only have 25% of their original remaining life span left.
* In ''Manga/ThePrinceOfTennis'', no one's life is literally in danger, but junior high tennis is [[SeriousBusiness taken very seriously,]] so permanent physical damage may well be equal to death, or [[FateWorseThanDeath even worse.]]
** One of the earliest example is the Hadoukyuu, a powerful shot that hurts the arm of whoever hits it, as well as whoever is bold, or stupid, enough to try to return it. Used initially by Ishida Tetsu, who then passes it on to Kawamura Takashi, who develops a Dash version which is even more destructive. Then we meet the big brother of Tetsu, Gin, who has [[Mystical108 108]] levels of this move, of which level ONE is equal to the Dash version. Despite this, Gin loses to a fluke which is widely seen as [[MyKungFuIsStrongerThanYours a cop out.]]
** Tezuka Kunimitsu, widely regarded as one of the best players in the series has several {{Deadly Upgrade}}s. The Zero-Shiki Drop Shot and the Invincible Tezuka Zone place considerable stress on his left arm, but he still manages to go into a 37-35 tiebreaker, which is ridiculous for tennis. Later on, these both get upgraded into a serve version, making it literally unreturnable, and a Reverse Zone, which places SIX times the burden on his arm, making it turn a deep purplish hue by the end of the match. Obviously, none of his teammates want him to sacrifice his arm for the sake of victory, seeing that he has a promising professional career in his future. Ironically, in the matches where these are first unveiled, he loses, creating blots on an otherwise perfect official record.
** Another ridiculous technique will ruin one's shoulders, since these players have only hit puberty, and their bodies are still maturing. Yet another one ruins the player's legs, because he's been running at hyper speeds. There's even a player who literally becomes a devil, complete with bloodshot eyes and newly-turned-white hair.
** The most ridiculous example of this trope is the Pinnacle of Perfection, which appears to take the player who achieves this state to a higher plane of existence, but at the cost of losing all of his memories, including those of how to play tennis, rendering this upgrade, at face value, essentially useless. Currently, not surprisingly, the main character is believed to have obtained this state, seeing as how the manga is finally coming to an end. However, it turns out the Pinnacle of Perfection has no drawbacks. It is revealed that Ryoma used it during his match with Kintarou, before losing his memories. Losing his memories was because of an accident, not because of the Pinnacle of Perfection.
* ''Manga/OnePiece'':
** Tony Tony Chopper (a reindeer who can become a humanoid with the power of the Person-Person Fruit) can access four additional forms besides his animal, human, and hybrid forms with the use of pills called "Rumble Balls". However, if Chopper takes more than two Rumble Balls within six hours, he turns into a mindless hulking monster. Not only is this move dangerous to those around him (due to his mindless rampaging), but it causes internal bleeding (shown by the blood coming from his mouth, despite never being harmed), making it lethal for himself as well. It's because Chopper's Monster form requires massive amounts of energy to keep going, far more than Chopper actually has. In addition, Chopper is essentially unconscious while he's in that form so he can't leave it on his own. After the TimeSkip, he learned how to control it, but it still renders him too weak to move after using.
** Gear Second not only drains Luffy's stamina faster than normal, but according to Rob Lucci, it shortens his lifespan by increasing his metabolism. Lucci also states that if Luffy were not a rubber man, his heart would explode if he used the technique. Of course, if he wasn't made of rubber, he probably couldn't do it in the first place. It is likely that similar to Chopper above, his greatly increased stamina after the TimeSkip renders these limits moot.
** And way before all that, the Alabasta arc had a very {{anvilicious}} parody of this trope in the form of the Kicking Claw Squad. This consisted of four Alabasta royal guards that took an elixir known as the Fatal Fuel. The good part is that it hugely increased their strength, allowing them to break the bracelets on their arms by merely flexing their muscles. The bad part is that said elixir will kill them in minutes. The worst part is that [[BigBad Crocodile]] [[ExploitedTrope exploits]] this by refusing to fight them, [[TacticalWithdrawal instead retreating to safety and waiting for them to die]], mocking them as they die a dishonourable death.
* These pop up fairly often in ''Franchise/{{Digimon}}'':
** In ''Anime/DigimonAdventure'', when Greymon was pushed by Taichi into evolving, he changed into the dark [=SkullGreymon=], a mindless monster. When he evolved "naturally", he became his true Perfect form, [=MetalGreymon=].
** Takato in ''Anime/DigimonTamers'' had a similar experience: When [[spoiler:Beelzebumon kills Leomon,]] Takato's rage and grief is so intense that it corrupts [=WarGrowlmon=]'s evolution and he becomes Megidramon, which would be fine, except Megidramon's power is ''so'' great, that it begins to destabilize the fabric of the Digital World. It's not until Takato gets a hold of himself that Megidramon devolves back into Guilmon, and together, they [[FusionDance Bio-Merge Evolve]] into Dukemon/Gallantmon.
** In ''Anime/DigimonFrontier'', the Beast Spirit evolutions ended up being {{Deadly Upgrade}}s in a sense because the kids couldn't control the power at first and went berserk, wrecking areas and nearly killing each other. Of course, they eventually got over this problem. Only Zoe and [[spoiler:Koichi]] were able to control their Beast Spirits right away ([[spoiler:in Koichi's case, when he gained his true Spirit forms]]).
** ''Anime/DigimonDataSquad'' and its associated tamagotchi introduces Burst Mode, a DeadlyUpgrade version of Season 2's Mode Change. In the tamagotchi, if the Digimon runs out of "Burst Points," it dies. [[spoiler: In the anime, Masaru combines Takato and Taichi's mistakes, and mis-activates Burst Mode, changing his partner [=ShineGreymon=] to Ruin Mode, who quickly ran out of energy and died. Though, since the minions of [[StoryArc the arc's]] BigBad died first, he got better thanks to ResurrectiveImmortality.]]
** In the ''Manga/DigimonXrosWars'' manga, [=MachLeomon=] upgrades himself with the Abyss Truffle, which an elder Mushmon explains to be this. The Abyss Truffle gives [=MachLeomon=] both a PowerHigh and a regular high along with his new form, but would have killed him had he not been finished off by Shoutmon X3 first. If he'd been weaker, using it would have killed him instantly.
* In the DarkerAndEdgier ''Franchise/{{Pokemon}}'' light novel ''LightNovel/PocketMonstersTheAnimation'', Nurse Joy advises Ash against evolving Pikachu because ones that evolve into Raichu too young end up giving themselves heart attacks from being unable to control their electricity output, leaving them traumatized enough to avoid using their powers entirely and slowly kill themselves.
* Ichigo in ''Manga/{{Bleach}}'' is able to throw around massively powerful ''Kuroi Getsuga Tenshō'' (energy blasts), but doing so too often risks losing his personality to his [[SuperpoweredEvilSide Hollow side.]] He can allow his Hollow side to come out in times of distress, whose violence and power is usually enough to annihilate any opponent. After training with the Vizard, he can even do so without going [[SuperpoweredEvilSide evil,]] but only for eleven seconds.
** And in recent events, he's [[spoiler:transformed into a sort of Super Hollow, capable of defeating Ulquiorra easily. However, evidently he's gone completely berserk, and has (at least temporarily) given in to his Hollow side.]]
** [[spoiler:Ichigo eventually learns the Final Getsuga Tensho, the final form of his zanpakuto which surpasses even his Bankai. He puts it to use in his final battle against Aizen, allowing Ichigo to defeat him. The downside of this power is, once he uses it, he loses his Shinigami powers permanently.]]
** Meanwhile, [[spoiler:Ishida's final "upgrade" is one-use-only. He removes his 'Senrei' gloves, which make it more difficult to collect spirit particles- therefore someone who can collect the normal amount of particles while having the glove on has reached the pinnacle of Quincy power. When the gloves are removed, that limit is removed, so a much greater amount of particles can be collected. However, this amount is far too much for his body to handle, so his body [[BroughtDownToNormal seals his powers altogether.]] He gets his power back later, though, by pushing himself to exhaustion so that being shot near the heart reopens the paths to his power. This leaves him with a Quincy "cross" shaped scar where the arrow struck.]]
** Cirucci Sannderwicci gains the ability to bypass her released form's drain on her spiritual energy by discarding her wings, enabling her to use a large energy sword from her tail at the cost of never being able to use her wings again.
** The ultimate technique of Komamura's clan, [[spoiler:the Human Metamorphosis technique, temporarily grants them an immortal human body.]] To perform the technique, they have to cut out their own heart. [[spoiler: It, too, is one-use only, leaving the user a mortal non-anthropomorphic animal.]]
* EVA-01 and EVA-02 in ''Anime/NeonGenesisEvangelion'' were given strength and capabilities in accordance to the Sync Ratio between the pilot and machine, but the higher the values, the more likely that the pilot might [[{{Synchronization}} suffer the injuries the mecha did,]] go insane, or [[spoiler:get absorbed into the mecha.]]
* Franchise/SailorMoon can transform into Princess Serenity and blow the BigBad away with her [[AppliedPhlebotinum silver crystal]] and ThePowerOfLove...but she dies every time from all the energy output.
** In the live-action ''Series/PrettyGuardianSailorMoon'', she can upgrade to Princess Sailor Moon, in which she is possessed by Princess Serenity and has access to great power. Unfortunately, Princess Serenity is something of a sociopath in that series that doesn't care if she hurts anyone to kill the monster of the day, constantly plays a harp that is actually feeding the energy of Queen Metaria and accelerating the destruction of the planet, summons monsters to beat the crap out of her friends when they try to stop her...oh, and she's perfectly happy to ''destroy the world and kill everyone on it'' if anything happens to her lover. Needless to say, this makes Princess Serenity as much of a threat as the Dark Kingdom at the end of the series.
* The anime ''Manga/{{Claymore}}'' almost entirely revolves around the caveat that when the series' eponymous half-demons overclock their powers too far they turn into monsters far more dangerous than those they were created to destroy; some of the more powerful of these 'awakened ones' are the primary villains of the series.
** However, Claymores who have gone past their limit and managed to return to normal are able to do so more easily, allowing them to use more of their power, provided they don't go TOO far past their limit. However, it's theorized by said Claymores that they may still be awakening because of it, just very, very slowly.
* The ''[[Anime/MegaManNTWarrior Rockman.EXE]]'' anime series did this in their final two seasons, with a twist - Rockman didn't control his transformation, a child named Trill did. Sometimes this worked out, like when Rockman was fighting the very giant Cyber Beasts he was drawing his transformation from; and sometimes it didn't, forcing the other characters to devise a complicated plan to capture him and settle him down which usually failed several times.
** The parallel game, ''VideoGame/MegaManBattleNetwork 6'', played with the same mechanic. In battle, you can take the beast form for three turns, after which you drop into a weakened, untransformed state. Of course, you can do it again, which puts you totally out of control and attacking randomly, and if ''that'' doesn't win you the battle, you go into a state so tired and weakened that you have to continue the battle at a pretty significant disadvantage. Of course, it doesn't stop the writers from arranging chapters where Mega Man is forced into uncontrolled transformation and you have to lug some other character over to put him down and get him back to normal.
** In 4 and 5, the player can gain certain "Dark Chips". They are a variation of normal chips (there's Dark Fan, Dark Vulcan and so on), but with immense power and ability to change the tide of a fight. There are, however, two drawbacks. One is that every time Mega Man uses the chip, his HP lowers by 1 permanently. Also, the more he uses Dark Chips, the faster he will be placed under "Dark Mega Man" state. He becomes a super-powerful rampaging machine that randomly uses Dark Chips, moves chaotically and doesn't stagger when being hit, but he also slowly loses HP until he reaches 1, at which point he goes back to the normal state. The only saving grace for 4 is the ability to have multiple playthroughs, so you can recollect HP upgrades and basically negate the HP downs. It's made a bit better in [=BN5=], where you sacrifice a chip of a certain type to go into a cross form, but using them regularly will permanently shave 1 HP off your max limit per use.\\
Later on, Mega Man gets the ability to do this with Dark Chips. Chaos Unisons (as they're called) allows Mega Man to use (most) effects that he can use in a regular Cross, with the addition of being able to use the Dark Chip sacrificed as a ChargedAttack. Fail the charge, though, and Dark Mega Man will show up-- on the enemy's side. In addition, you only have the ability for one turn, the failure window for the charge doubles each time you use the Dark Chip, and you lose the ability to use the corresponding normal Cross for that battle. [[GameBreaker And then you realize the charge releases instantaneously if you let go of the fire button while the game is paused, and you can see what state the charge is in...]]
* In ''Manga/RaveMaster'', Sacrifar, the appropriately-named 9th form of Ten Commandments sword bestows the wielder with overwhelming power, at the cost of being gradually consumed by the sword both physically and mentally. At its first appearance, there is quite a bit of LampshadeHanging over how crazy the man who forged the sword was to put in that form. That said, the sword in question was meant to be used first by Shiba, and Haru was the one who first used Sacrifar in the series; however, after Haru gets a new Ten Commandments meant for him to use, he never uses Sacrifar again.
** A member of the Dragon Race (like Let, Julia, or Jegan) can invoke the great power of the Dragon God, but only by sacrificing their lives to the deity.
* The lead character of ''Franchise/LyricalNanoha'' has a tendency to do things that are really bad for her, especially in the second series. This goes from using the dangerously explosive Cartridge System to using her WaveMotionGun's full-power form, Excelion Mode. It's revealed in the third series, ''Anime/MagicalGirlLyricalNanohaStrikers'', that [[spoiler:at some point during the TimeSkip this all caught up with her, and what should have been a [[OnlyAFleshWound minor injury]] in battle caused such extensive damage that she had to spend months learning to walk again.]] She later has her Excelion Mode replaced with a weaker Exceed Mode, which is a more traditional SuperMode. At the end of the series, however, she deploys a new Blaster Mode, which [[CastFromHitPoints causes direct physical damage to herself and her weapon as a result of drastically boosting her power]]. Of course, by the time she receives this, she already has a known tendency to use techniques and upgrades that pushes her body to the breaking point, so instead of telling her not to use it, her [[TheLancer long-time partner]] tells her not to ''over''use it.
* In ''Anime/YuGiOh'', the Spell Power Bond can double the attack strength of any Machine-type Fusion monster; however, at the end of the turn in which it is used, it decreases the user's Life Points (which, in GX, where it was introduced, started at 4000, making it much more dangerous than the real card) by the original attack power of the monster. Possibly another example of ExplosiveOverclocking. Similarly, the Spell Limiter Removal can double the attack strength of all the user's Machine-type monsters for one turn. After which, they are destroyed.
* In the ''Anime/{{Witchblade}}'' anime, the use of Witchblade is shown as too taxing for a human body, and wielder of a Cloneblade sooner or later [[PhlebotinumBreakdown falls]] a victim to rapid and irreversible body deterioration ending with spectacular SuperPowerMeltdown. In some cases it will also corrode their mind as well. Both original and {{Evil Knockoff}}s are {{Clingy MacGuffin}}s, of course.
* In ''Manga/OutlawStar'', the three rare Caster Shells, numbered [[FourIsDeath 4]], 9, and [[ThirteenIsUnlucky 13]], are so powerful that it also takes away part of Gene Starwind's life whenever he fires one. On a side note, 4 and 9 are considered unlucky numbers in Japanese culture, and 13 is an unlucky number in western culture.
* Guts from ''Manga/{{Berserk}}'' has the Berserker's Armour, which draws out the full physical strength of the wearer. However, the armour also draws out the SuperpoweredEvilSide of whoever wears it, and while the wearer can ignore pain, this is a double-edged sword, since the strength of whoever wears the armour will badly damage their body. Also, the armour mends broken bones by ''piercing through flesh with spikes''. This led to the previous owner dying of blood loss after every single bone in his body was broken.
* Upgrading one's Alter Power in ''Anime/{{S cry ed}}'' includes the risk of not only dangerously messing up the user's body, but also eventually draining the user's entire life force. As the series goes on, the Upgraded Alter Power users show more and more damage to their own bodies from continual use. Kazuma and Ryuhou show scars across their bodies where their Alter Powers bond to their bodies, while Straight Cougar is actually ''unable to walk properly because of how messed up his legs are.''
* ''Manga/{{Hellsing}}'':
** Alexander Anderson uses the Nail of Helena on himself and becomes [[spoiler:a plant-thing far more powerful than his normal self]] but using it requires him to stab himself in the heart.
** Likewise, [[spoiler:Dark Walter is vastly superior to his elderly, human self in terms of speed, dexterity and skill (he's able to slice a skyscraper in half at one point). But his endurance for prolonged combat is quite poor as he quickly develops an IncurableCoughOfDeath very soon after engaging Alucard in battle, due to the fact that his [[BodyHorror body is breaking down because of the Doctor's hasty surgery]].]]
* In ''Manga/NegimaMagisterNegiMagi'', Negi learns a BlackMagic version of this. He gets to equip spells to his body to boost strength and/or speed, depending on what he equips, at the cost of damage to his ''soul''. The arc's BigBad refers to it as "magical doping".
** His master later reveals that [[spoiler:its turning him into a demon.]] He is almost eerily nonplussed by that revelation, something he handwaves by pointing out that, technically, his master is [[spoiler: a demon]], and she's still a good person.
** [[spoiler:Chao Lingshen]] also has one of these, in the form of magical runes carved on her body that release a titanic magical power when unlocked. However, doing so causes her intense pain whenever she casts something, so they're normally sealed. Akamatsu has stated that it's in some way related to the BlackMagic Negi later uses.
* In ''Manga/FairyTail'', Natsu consumes the [[spoiler:Etherion magic absorbed by the Tower of Paradise]]. This brief and HUGE power boost gives Natsu the edge he needed to give the [[spoiler:fake]] BigBad Jellal a beatdown. But at the start of the following arc Natsu suffers narcolepsy due to consuming non-fire related magic.
* In ''Manga/KenichiTheMightiestDisciple'', there are two kinds of aura used while fighting: Dou (letting your anger burst out) and Sei (keeping a calm and level head). It's possible to combine the two for more power, but doing so rips apart the muscles and puts heavy strain on the mind. Of the two who've used it, one ended up in a wheelchair. The other one [[spoiler:died, but for unrelated reasons.]]
* In ''Anime/TekkamanBlade'', D-Boy/Blade's constant transformation from human to Tekkaman and back is disintegrating his central nervous system (the other human-based Tekkamen were also going to die as a result of incompatabilities). When he gets his SuperMode upgrade, in at least the Australian version "Teknoman", the main villain comments that this upgrade causes death within a few months, and it is shown to cause D-Boy/Blade to lose memories as a result of transformation instead of having its previous deleterious effect on the central nervous system.\\
So long as a Tekkaman was fully converted with an intact crystal then they could switch between forms with no penalty. The problem was that early on in the series D-Boy's crystal was broken and although the shards were placed on Pegas to allow transformation it was flawed and and repeated use of the flawed transformation was what caused nervous system damage to him. It also meant that so long as he used the broken crystal he'd have a time limit before going berserk. It was also true that if a human and Tekkaman plant weren't completely compatible, then they'd eventually die (which is what happened to D-Boy's sister).
* In ''Manga/{{Mahoromatic}}'', combat android-turned-maid Mahoro has an Ultimate Attack that is actually fueled by her life-force, so every use of it shortens her already brief lifespan.
* Subverted in ''Manga/DragonHalf''. Mink's power grows constantly when she passes her metamorphosis, due to be a red dragon/human hybrid. However, if she achieves her maximum might and completes her metamorphosis, a prophecy states that "a black monster shall appear". A magic bracelet allows her to stop her power development at will, but against the stronger enemies she keeps facing, she is forced to [[TimeToUnlockMoreTruePotential unlock more potential]]. When she finally unleashes all her power to save her true love, the transformation comes? The black beast finally is showed in front of them all. [[spoiler:As a tattoo on Mink's butt.]]
* Using the black blood in ''Manga/SoulEater'' is this, as the advantages given by that kind of madness (hardening the blood against injury, not caring about injuries you're receiving or giving because you're out of your mind) are negated by the consequences of doing so too much; the insanity could become permenant. The heroes eventually get around this by being able to control insanity for their own uses, but whether this trick would have continue to work is unknown.
** The Nakatsukasa Purpose is originally seen to be this, but only because Black Star was going about using the Demon Blade mode the wrong way. Until he was beaten into re-thinking his approach, he was told explicitly that over-using the Forbidden Technique would kill him. Once Black Star faces the will inside the Demon Blade and declares that he will strive on the path of warrior to resolve the despair of fallen warriors, he became capable of using the mode without issues.
** Kid's Sanzu Lines are an unusual an example of this. It was implied since this was first brought that he will get the upgrade that would prove deadly to his father. If so, Shinigami is remarkably (well, not so surprising coming from him) upbeat about the prospect. After defeating Noah with this Super Mode, Kid seems aware of the Lines connection to his [[TrulySingleParent father]], but does not seem to know what effect the temporary upgrade has on Shinigami. [[spoiler:Said effect actually entails that Shinigami-sama -a Great Old One- died.]]
* Speaking of blood, [[SuperhumanTransfusion vampire blood]] in ''Manga/RosarioPlusVampire'' is this to a human (Tsukune) who receives it. First, it either heals the recipient's body completely or kills him, which already makes it [[EmergencyTransformation a last resort]]. Then, it [[HourOfPower temporarily]] gives him the powers of a vampire, but after so many uses, the change becomes permanent. Unfortunately, the blood gradually breaks down his body and mind from within, and had its progress not been stopped by a PowerLimiter, he would have been turned into a [[TheBerserker rampaging]] [[OurGhoulsAreCreepier ghoul]]. It still surfaces occasionally.
* [[BewareTheNiceOnes Cho Hakkai]] from ''Manga/{{Saiyuki}}'' can turn into a nearly unbeatable super-powered youkai by taking off his [[RestrainingBolt power limiters]]... but runs the very real risk of "losing himself" to the Minus Wave that's [[BrainwashedAndCrazy brainwashing]] weaker-willed youkai.
** And the same goes for Son Goku of the same series, much like the ''Franchise/DragonBall'' example above-- fitting, since they're based on the same character from mythology.
* In ''Manga/YuYuHakusho'', Hiei's [[DangerousForbiddenTechnique Dragon of the Darkness Flame]] goes given a second use beyond basically an out of control beam attack- Hiei can let it hit him in order to absorb its power. The catch to this powered up state? It leaves him utterly drained and basically comatose for a time. Good thing he's got teammates to look after him.
* ''Anime/BraveCommandDagwon'' has Daidouji En becoming Super Fire Dagwon only 3 times due to this. That form, while immensely powerful, requires a burst of energy from the Dagbase to even start the combination and is basically the equivalent of one person controlling two bodies - it eats up the user's stamina like nothing else. He's tough and a walking embodiment of willpower, but it still left En in a hospital bed after each use.
* [[spoiler: Edward]] uses this in ''Manga/FullmetalAlchemist.'' After receiving a massive injury during a fight, he [[spoiler: uses his soul as a mini-Philosopher's stone, stopping the blood loss in exchange for a few years of his life]].
** Toward the end of the [[Anime/FullmetalAlchemist 2003 anime]], Al [[spoiler:becomes a Philosopher's Stone]]. After that, any use of alchemy costs him a piece of his body.
* In ''Manga/CeresCelestialLegend'', the villains have developed some sort of serum to activate/boost the powers of potential ten'nyo, but once someone is injected with it their body begins to break down,a process that seems to be accelerated by frequent use of ten'nyo powers.
* In ''Anime/PuellaMagiMadokaMagica'', [[spoiler: becoming a MagicalGirl grants you magic powers, but the more often you use them, the faster you fall prey to TheCorruption and eventually turn into a witch. The only way to avoid that fate is to die before it happens.]]
** [[spoiler:Madoka]] is an extreme example of this, having been repeatedly buffed by [[spoiler:a time-travelling Homura]] to the point that activating her powers even once would cause her to become [[GodzillaThreshold Godzilla's worst nightmare]] moments afterward. [[spoiler:She eventually subverts this by making a contract specifically to erase all witches from every point in every timeline--including the one she'll become.]]
* ''Manga/OtogiMatsuri'': The power granted by the Phoenix-like god named Suzaku is a mystical bow that appears as an extension of Yousuke's arm, that fires arrows of light with the power to kill evil spirits in a single shot. In exchange, Suzaku declares that it will take Yousuke's "future"... meaning that the young man only has a year left to live.
* [[spoiler: Break]] from ''Manga/PandoraHearts'' has this. [[spoiler: The more he uses his [[EldritchAbomination Chain]], the more it destroys his body...he's already gone blind and has repeated moments of BloodFromTheMouth.]] And yet, he's still [[HandicappedBadass extremely badass]].
* In ''Anime/KillLaKill'', protagonist Ryuuko's [[ClothesMakeTheSuperman sentient uniform, Senketsu]], enhances her physical strength, durability and agility to superhuman levels, but constantly drains her blood to the point of unconsciousness, [[spoiler: until she stops subconsciously rejecting the embarrassingly {{Stripperiffic}} outfit at which point the disadvantage is negated]].
** Antagonist Satsuki gains the same powers but is able to avoid this drawback due to knowing how the godrobe works and [[spoiler:having no shame]]. Later in the series however [[spoiler:we learn that using the godrobe for long periods takes an enormous toll on her health which she has been suppressing by sheer force of will]].
** In the final episode [[spoiler: Senketsu absorbs the power of "Absolute Domination" becoming supremely powerful at the cost of overloading and being destroyed shortly afterwards]].
* In the first ''Anime/TenchiMuyo'' movie, ''Tenchi Muyo In Love'', Achika (Tenchi's mom in the ''Anime/TenchiUniverse'' continuity) ends up unlocking her Juraian powers, then proceeds to blow it all striking down KAIN. This ended up cutting her lifespan so much that she dies when Tenchi is only 3.
* ''Manga/JoJosBizarreAdventure'' has a few. One of the most notable is in Part 2: Wamuu's final attack, "Converging Squall", draws air in and out of tubes in his chest, creating razor-sharp winds that hit everywhere around him. However, the friction created by this attack slowly tears his body apart from the inside. Wamuu only dares to use it against Joseph after already losing his arms and taking a Hamon blow to the chest, which will kill him anyway if he doesn't finish the fight in minutes.
* In ''Manga/HunterXHunter'', [[FunctionalMagic Nen]] is an example of ConditionalPowers. The greater the restrictions placed on a Nen user, the greater the power. [[spoiler:Main character Gon]] crosses the DespairEventHorizon during the Chimera Ant Arc and, in his own words, "uses everything" to make himself strong enough to crush the one who pushed him over the horizon. At the cost of never being able to use Nen again and an extremely shortened lifespan, he is temporarily aged to adulthood and gains Nen that rivals the Chimera Ant King's.
** [[spoiler:Kurapika]] also has a similar form of this with his own contract, [[spoiler:every time he uses emperor mode, which makes him a master of all 5 Nen Types and essentially a god, each second he spends in the form shaves weeks off of his life, and if he were to use it for so long, he'd eventually die with how much of his life is cut off.]]
* In the anime adaptation of ''Manga/MagicKnightRayearth'', Alcyone tricks Ascot into giving this to one of his pet monsters. It hugely increases its power and freezes the whole landscape, but before long it turns it into a small iceberg with PowerIncontinence and it eventually shatters. Ascot is ''not'' happy.
* The Griselda and Libertus Hyper-Zoanoids are this in ''{{Manga/Guyver}}''. Libertus are designed to rip through other Hyper-Zoanoids like tissue paper while Griselda can, at short ranges, over-power the telepathic control of a Zoa''lord''. However to power those abilities they need to spend most of their time in nutrient tanks because there's no other way to absorb enough energy and even with that the stress on their systems is slowly killing them. (Predicted survival time is about two years).
* ''Manga/AttackOnTitan'' reveals that [[spoiler: consuming the cerebrospinal fluid of a Titan Shifter allows someone to become one themselves. Unfortunately, once this happens, they have only 13 years left to live. Their human bodies gradually break down until they die, complete with BloodFromTheMouth.]]
* ''Manga/MyHeroAcademia'' reveals that [[spoiler:One for All is this for Quirk users. Oh sure, they can accept without any issues and combine it with their own Quirk, but One For All doesn't just take the Quirk inside itself, it also puts incredible strain on the user's body that burns them out, using the analogy of an already-filled cup overflowing and breaking apart. Sadly, no one had an inkling until the fourth user spent twenty years as TheHermit trying to strengthen the Quirk and he found his life coming to a premature end and necessitating the transfer of the Quirk, and it wasn't until All Might did serious research that the vestiges within One For All put it all together. The only reason All Might and Izuku could use it to its full potential is because they were Quirkless, thus they could handle it and make it their own without having their life force sapped (using the analogy of an empty cup that can be filled safely). What makes this even sadder is that Quirkless could be gone within a generation, and even if that didn't happen, they could never handle the all power One For All has accumulated over the years, thus Izuku might most likely be ''the last holder of One for All'']].

* In 90's ''Franchise/{{Godzilla}}'' films, the King of Monsters can fire a much stronger version of his blue atomic beam that is red and has lightning spiral around it if he absorbs enough energy. The down side is if he absorbs too much power he will turn into a meltdown mode that will cause a SuperPowerMeltdown that can burn up the atmosphere and kill all life. In ''Film/GodzillaVsDestoroyah'', he does end up going into meltdown mode. It's only by his son Godzilla Junior does the Earth survive: [[spoiler: when Burning Godzilla finally has a total meltdown, Junior is forced to abosrb the excess radiation, maturing into a new Godzilla.]]
* In ''Film/GodzillaKingOfTheMonsters2019'', Godzilla is left severely weakened after taking a direct hit from the US military's Oxygen Destroyer missile during his second fight against King Ghidorah. While the Monarch scientists determine that Godzilla's injuries are not life-threatening, it will take him several years to naturally recover from them and the rest of the world will not survive that long with Ghidorah still running loose, so they detonate a nuke right next to Godzilla in order to instantly heal him for the final battle against Ghidorah. Once Godzilla and Ghidorah engage each other in said battle, it quickly becomes apparent that the nuke healed Godzilla too much, resulting in his radiation levels overloading to the point of causing a meltdown that will wipe out not only the city of Boston (where the battle is taking place), but a significant portion of the surrounding region. Fortunately, Mothra arrives on the scene and performs a HeroicSacrifice that stabilizes Godzilla's radiation levels and unlocks his SuperMode to finally eliminate Ghidorah.