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[[quoteright:350:[[Manga/DragonBallZ http://static.tvtropes.org/pmwiki/pub/images/nbmtcak.png]]]]

->''"I don't remember much after the explosion, but somewhere amongst the planetary debris the core of my being still existed, one living cell survived, and that is all I needed for my regeneration... Soon that living cell began to multiply into many, it wasn't long before I became conscious of my transformation, I could feel every part of my body growing, crackling with new life and energy. My shapeless mass began to sprout new limbs, first my legs, then my arms, and in no time, my whole body was restored!"''
--> -- '''[[MeaningfulName Cell]]''', ''Anime/DragonBallZ'', having just survived his own [[EarthShatteringKaboom Earth Shattering Kabooming]] TakingYouWithMe thanks to this trope.

%% No more than one quote, please. Put the rest on the Quotes tab.

The worst kind of unkillable enemy, there's the creature who cannot be mortally wounded, because he has a HealingFactor ramped UpToEleven. Every injury simply regenerates, from lost limbs, to a blown off torso, to a broken neck. Even when you think you've [[KilledOffForReal completely killed him]], he comes back, because you missed a bit of flesh that was able to replicate itself into a new body.

This is rarely ever a trait of the hero; it is more often a power a villain has that marks him as being too powerful and resilient for the heroes to overcome, forcing them to find a creative way to beat the villain or gain a PlotRelevantPowerUp.

If not properly explained, or given to a character who doesn't really seem worth it, it can become an AssPull. No matter how well done, it will have audiences (and characters themselves) screaming "WhyWontYouDie!"

Why every loose cell or drop of blood shed by the character doesn't [[AsteroidsMonster generate a copy of them]] is not generally addressed. In a supernatural setting this can be {{handwave}}d with some talk about souls or lifeforce, though one still wonders how the various bits go about deciding which one of them gets to do the regeneration. Bonus points if the character/creature in question somehow retains all of his memory and personality (which are stored in the brain - no brain, nothing to restore all that data from!).

Also, per mass-energy conservation, this process should either require some sort of mass to absorb and convert into new cells, or a ''lot'' of energy to convert to mass.

Expect this from all sorts of enemies, from demons, aliens, to androids made of {{Nanomachines}}.

A form of NighInvulnerability. A character who can regenerate this way ''and'' is TheAgeless has CompleteImmortality. See ShapeShifterBaggage and the necessary GeneticMemory. Also see GoodThingYouCanHeal and ImmortalLifeIsCheap. Related to PullingThemselvesTogether.



[[folder:Anime & Manga]]
* [[TropeNamers Cell]] from ''Anime/DragonBallZ'' was a biological android with many of the main characters' abilities coded into his DNA, including Piccolo's regeneration and Freeza's ability to survive in very harsh conditions. Therefore, he doesn't have to worry about dying if... say... the upper half of his body gets blown off. In fact, after initially losing to Son Gohan, he tries to blow himself up and destroy the planet. After Goku sacrifices himself to teleport Cell somewhere far away from Earth, Cell surprises everyone, including himself, by regenerating quite literally from a single cell.
** Depending on the translation, Cell's couldn't regenerate from just any random single cell, but from a group of "core cells" in his brain. This caused a potential plothole, since he was actually beheaded by Goku at one point. The English anime kept the visual of the "core" in his brain but changed the dialogue so that ''any'' of his cells could reform his body.
** Cell has an unusual twist on this; his Saiyan cells grant him a zenkai whenever he recovers from gruelling injuries (such as losing a limb), with the power boost being proportional to the injuries sustained. Applying that to his coming back ''from a single cell'' results in him becoming several times more powerful.
** The next villain after that, Majin Buu, is a murderous, supernatural djinn, who can reform himself from a single piece of himself, and can reform himself if he is blown apart into a million pieces, or even air vapour. A single cell? All he needs is a single ''molecule''. Planetary explosion? Give him 3 seconds. Blown up to shreds, the shreds then being vaporised just to make sure. Give him 3 god damn seconds. It took a CombinedEnergyAttack with power from ''every non-evil, non-dead character in the series up to that point'' to kill him.\\\
It's interesting to note that his regeneration becomes more powerful (or at least faster) with every transformation. Fat Buu already fit this trope, but it was a fairly slow process. Super Buu was able to regenerate at incredible speed, though there was implied to be mental limits that Gotenks almost reached and during his battle with Vegetto in the anime it seemed to start slowing down as he got his ass utterly wrecked to the point Vegetto actually pointed out he hadn't regenerated from an injury yet and ''Buu didn't even notice''. Finally, Kid Buu could regenerate seemingly instantly from having his entire body destroyed, with no visible limits aside from complete destruction of every molecule of his being. Kid Buu's being the fastest could be justified by virtue of being the original form of Buu.
** Baby, a villain from anime exclusive, ''Anime/DragonBallGT'', had similar regenerating powers. He is destroyed for good when Goku blasts him into the sun, eradicating every last one of his cells.
* Alucard from ''Manga/{{Hellsing}}'', who can also use his spilled blood as a deadly weapon with no adverse effects. More than once is he reduced to a fine red mist before regenerating fully. To elaborate, in the ''Hellsing'' universe when a vampire drains a victim of their life's blood they absorb the victim's soul. Among other things this gives the vampire what amounts to [[OneUp an extra life]]. Alucard has feasted upon so many battlefields that his extra "lives" number in the hundreds of thousands by the series. However, Alucard can turn his "servants" loose as a literal army, which leaves him alone and vulnerable to a stake through the heart, but he remains a formidable opponent even then. If you wipe out his army and/or fail to destroy him, he'll drink more blood, rejuvenate completely and gain more lives - like he did when he summoned and absorbed blood from ''the entirety of London's population.'' [[spoiler:He was finally brought low when that meal was "poisoned", turning his gathered souls against him and deleting him from the world. At the time of this CriticalExistenceFailure, Alucard had three million, four hundred and twenty-four thousand, eight hundred and sixty-seven "lives" from the London battle. He sacrificed all but one and gained an even stranger and stronger immortality, though the process took him decades to complete.]]
* Immortals in ''LightNovel/{{Baccano}}'' effectively work this way, although except in the case of their bodies being burned or dissolved, they don't regenerate so much as all of their tissues, any spilled blood included, are simply drawn inexorably back together into the proper form. Even when burned or dissolved with chemicals, however, they can still fully recover - [[MadScientist Fermet]] [[ForTheEvulz checked]].
** Szilard's done his own research on the subject, and discovered that immortals [[PullingThemselvesTogether pull themselves together]] on a ''molecular'' level - set an immortal on fire, and the resulting smoke will return to the burned flesh once regeneration kicks in.
* Yakumo from ''Manga/SazanEyes''. He was turned into a Zombie Wu, an immortal undead slave, when Pai, the last of the Sanjiyan, sucked his soul into herself to save his life. His HealingFactor is so powerful he was once able to regenerate from being blasted into a bloody mist.
* Elder Toguro from ''Manga/YuYuHakusho'' does this, but he explicitly says that the only thing that will kill him is by destroying his heart or brain. Simple enough, right? Wrong. He's able to move around all his organs and body parts to wherever he wants in his body and can even ooze through cracks in the ground. Only two characters in the series manage to defeat him: Kuwabara (after transforming his LaserBlade into a Laser ''Racket'' in order to squash his entire body) and later Kurama (giving him a FateWorseThanDeath by planting on him a monstrous tree that never stops harassing its victim until his or her death, which will never be the case with Elder Toguro).
* The ''Manga/{{Guyver}}'' can do this. Aptom from Guyver can also do this, although [[ImAHumanitarian he requires Zoanoids to alter into more of his body mass]] (rather like The Thing, under {{Film}}). As a bonus, this also [[PowerCopying lets him use those Zoanoid's powers]]. The "why doesn't every part of him regenerate into him" issue is addressed - this ''will'' happen if they have access to sufficient biomass, but all copies of Aptom have a HiveMind and can merge or split at will. Eventually, a villain finds a flaw in his power: [[spoiler: after Aptom is nearly killed, his non-sentient remains are exposed to a Zoanoid which contains a fake "Aptom brain" and absorb it. His cells do not regenerate his brain due to thinking it's already present, thus allowing the villain to control Aptom's body through the fake. Sho questions why "Evil Aptom" keeps using an unwieldy WaveMotionGun while fighting him, and realizes that he has been using it to destroy any pieces of Aptom which were separated from the main body]].
* The [[EnemyWithout berserked Self-Defense program]] in ''Anime/MagicalGirlLyricalNanohaAs''. Getting [[TakenForGranite petrified]] and [[KillItWithIce frozen]] didn't stop its regeneration. Getting blown to bits by three {{Wave Motion Gun}}s didn't stop its regeneration. What finally killed it? [[DeaderThanDead A weapon that completely annihilates a target by distorting time and space over a wide radius]], [[spoiler: and it still would have come BackFromTheDead had the first Reinforce not performed her HeroicSacrifice]].
* Gemma the DepravedBisexual from ''Anime/NinjaScroll'' has regenerative abilities that may approach this level, but it's hard to say. In the movie, he reattaches his severed arm, reattached his head several years ago, reshapes his face after literally having it pounded into mush, and is finally [[AndIMustScream drenched in molten gold and plunged into the sea, sinking to the ocean floor in a hardened cocoon of metal]].
* Deoxys from ''Franchise/{{Pokemon}}'' is shown to have this ability as long as its brain, the gem-like substance that protrudes from its chest (Which is pretty much indestructible anyway), is still active. While it can regenerate lost limbs in just a couple of seconds, it has been shown that regenerating its entire body can take up to several years.
* ''Manga/{{Tomie}}'', the title character of a J-Horror manga series by Junji Ito and its subsequent film adaptations, can do this. She can also speed the process up by infecting the bodies of other women and turning them into copies of herself. A scene in an early storyline implies that she is able to do this by virtue of being extremely radiotrophic, somehow converting background radiation into mass as her growth was accelerated by a doctor's attempt to kill her with a radiation machine used to destroy tumors. Throughout the story its been proven that fire will [[KilledOffForReal kill Tomie for real]] and unable to regenerate (burned flesh are dead tissue)
* Genji Ikusabe from ''Manga/BusouRenkin'''s spear has the ability to regenerate his entire body very rapidly, even if the body itself is completely destroyed. Admittedly, it has the weakness that he has to be holding his weapon at the time.
* Rin, a rare protagonist example from ''Anime/{{Mnemosyne}}'' (due to encountering a spore of the Yggdrasill tree) has virtual immortality, including the ability to recover from any injury, even getting sucked through a jet engine. Of course, being able to regenerate and stay alive under all sorts of [[ColdBloodedTorture conditions]] can be... [[{{Squick}} bothersome]].
* Naraku from ''Manga/InuYasha'' becomes like this (he starts off able to regenerate, but with limits). At one point he's reduced to his head, one hand, and miscellaneous bits of flesh and has regenerated fully within a chapter.
* The Homunculi from ''Manga/FullmetalAlchemist'' seem to be able to do this when their Philosopher's Stone is intact. [[spoiler:Case in point: after one of his subordinates is grievously injured during a fight with the homunculus Lust, [[ColonelBadass Roy Mustang]] attempts to hit two birds with one [[{{Pun}} stone]] by forcibly removing Lust's Philosopher's Stone to kill her and using it to heal his friend. When the Stone is removed, Lust's body disintegrates, and Roy thinks he has won. [[OhCrap Cue utter horror]] when Lust's body begins to reform around the Stone in his hand.]]
** There is a limit to how much they can regenerate, as their stone's power is limited, so you can kill them permanently if you do enough damage. [[RasputinianDeath Which is a lot]].
** In the case of the Homunculi, the issue of why lost body parts and/or blood don't regenerate into copies is handled by the fact that a homumculus's Philosopher's Stone is the source of all its power. Thus, any part not connected to the Stone ceases to exist.
* Nurarihyon from ''{{Manga/Gantz}}''. Lets face it, without the gravity gun against this guy, you are screwed.
* ''Franchise/JoJosBizarreAdventure'' ''Battle Tendency'': This is one of Ultimate!Kars' {{Informed Abilit|y}}ies. It never comes into play, though - Kars is defeated via AndIMustScream rather than being destroyed.
** Body of the Foo Fighters from ''[[Manga/JoJosBizarreAdventureStoneOcean Stone Ocean ]]'' is [[WormThatWalks made out of sentient plankton]], and thus can survive as long as just a little piece of her body stays intact. On top of that this plankton can multiply very quickly, which allows her to grow full body back from said little piece in a matter of seconds.
* [[TheStoic Karkinos Rucan]] of ''Anime/HeroicAge'' was once completely destroyed, leaving only the core of his [[HumongousMecha Heroic Tribesman]]. [[GoodThingYouCanHeal He gets better]].
* ''Manga/{{Toriko}}'' has Elg of the Bishokukai, who fused with a legendary horse called a Heraku and as such can regenerate from a single cell, and do not cut him up into pieces because [[MesACrowd each piece will regenerate into an entire copy of him]]. [[spoiler:He dies anyway after Tengu Buranchi electrocutes all of his copies long enough that the Heraku's regenerative powers can't keep up with the damage.]]
* Acacia in the manga ''Manga/GreenWorldz'' regenerates from a single small flesh in chapter 51 despite being cut to pieces. Her {{healing factor}} is so strong that the hero has to resort to feeding her severely damaged body to a giant-size monster baby in order to get rid of her. Even after that, she is revealed to be alive in chapter 110 and managed to regenerate her body back.
* It's eventually revealed that this is the power of Shaz Domino in ''Manga/{{Bleach}}''. It's so strong that he, a projection made by Gremmy, ''generates himself a corporeal body'' and breaks free of Gremmy's control. Kira has to defeat him by repeatedly cutting him with his Zanpakuto [[FateWorseThanDeath until he is stuck in the ground and unable to free himself.]]
* Adolf ''Anime/{{K}}'' Weismann, the immortal Silver King, has this power. [[spoiler: He ends up being about [[BigGood as far from "villain"]] as it gets, though.]]
* [[BigBad Priscilla]]'s true strength in ''Manga/{{Claymore}}'' is her insane HealingFactor, which is pretty much based on ThePowerOfHate (some characters go as far as to say that Priscilla's powers are something one would expect from a god), it was certainly powerful enough to pull this trope off more than once. During one of the last confrontations Priscilla is literally cut into hundreds of pieces by Clare's Quicksword, only for her to just heal again, [[spoiler:devour a weakened Cassandra]] and come back stronger than ever. [[spoiler:In the final battle between her and Teresa, after that her regenerating abilities go temporarily out of control leading to [[BodyHorror plenty of Body Horror]], she ''does this again''! Multiple times in fact, as many of her scattered pieces produce each a full copy of Priscilla to attack Teresa with numbers. In the end Teresa has to use a move that basically all but pulverize Priscilla to keep her endless hatred from eternally regenerating]].\\\
This is also PlayedForDrama: [[spoiler:Priscilla still has a remnant of her Human self within herself, after her Awakening she has done everything possible to lead her Awakened form toward death, stabbing herself with her Claymore sword, messing with the likes of [[MonsterLord Isley of the North]], being eaten by an EldritchAbomination, but her hate was too strong for her to die. At the very end her Human half regains consciousness for a moment and thanks Teresa for being able to finally grant her death, and that she's sorry for all the trouble she created]].

[[folder:Comic Books]]
* ''ComicBook/TheDarkness'' had this once after Jackie set a warehouse and a few mooks on [[KillItWithFire fire]]. The Darkness survived by hiding in a tooth cavity; not knowing what else to do, the Darkness rebuilt Jackie.
* Lobo of Creator/DCComics, an alien mercenary who deviates back and forth from a PsychoForHire to a HeroicComedicSociopath, can revive himself from a single drop of blood. He once cloned himself an army this way, but, y'know, being all "sociopathic," they all killed each other until one remained (in non-bloody ways, like suffocating each other).
* One of the potentially toughest ''Franchise/{{J|usticeLeagueOfAmerica}}LA'' foes was always the Shaggy Man, a nearly-invulnerable, ten-foot-tall bionic android that could regrow any limbs it lost almost instantly. Luckily, it was utterly mindless and therefore easy to trick. Eventually, a crazed general dying of brain cancer transferred his mind into it. He hasn't shown up very often since, probably because they're running out of ways to get rid of an unkillable, unsubduable villain with the mind of a brilliant tactician. Part of this may be because General Eiling found out too late that TheMindIsAPlaythingOfTheBody. The Shaggy Man's tiny brain did not have a good effect on his mental facilities, and the Shaggy Man mostly just slept a lot. And yes, this does show a bizarre combination of the mind as the brain and as something beyond physical.
* Characters who can change their shape or are made of something inanimate, such as [[Franchise/SpiderMan Sandman, Hydro Man,]] and [[Franchise/{{Batman}} Clayface]], are often implied to be able to do this.
* ''Franchise/{{Superman}}'' villain ComicBook/{{Brainiac}} is constantly shown to be able to survive from the smallest remaining bit of his circuitry or computer program. This is taken to an extreme in the Franchise/{{DCAU}}, where the tiniest bit of Brainiac always survives, is stored somewhere, and manages to take over more technology and reform himself completely. He is then defeated, and the process repeats itself.
* Master Mold from the ''ComicBook/XMen'' acted much like Brainiac, storing backups of itself in out- of the way places. Its future "descendant", Nimrod, can rebuild itself if even a single molecule survives.
* Isstvan, from the comic adaptation of ''ComicBook/MythAdventures'' by Robert Asprin and Creator/PhilFoglio, gets blown up by a spell, and then rather squelchily reassembles. Nothing remotely like this happens in the original novel.
* ComicBook/{{Wolverine}}:
** He once regenerated from a single drop of his blood landing on an incredibly powerful MacGuffin that was making the villain of the month all powerful. As a result, his healing abilities were supercharged to the point that he could regenerate from a single cell. He was also still touching the item when he popped his claws, (to destroy it) making it reasonable to assume he either deliberately or subconsciously used its power to re-adamantiumize his skeleton.
** During the ''Civil War'' Saga, he was immolated down to his skeleton and regenerated. Later comics apparently had him trade in some of his healing factor to return from the dead.
** A common {{Fanon}} theory about how [[WolverinePublicity he can make so many cameos in other comics]] is that every time he loses a piece of himself, it eventually grows into another Wolverine.
* SelfDemonstrating/{{Deadpool}} also has regenerative properties. Unfortunately for him, it causes his cancer cells to regenerate rapidly too, causing him to be horribly disfigured and, well, not exactly sane.
* Slippery B'eeef, the villain of ''ComicBook/TheAuthority: Kev'' had this ability.
* Dr. Manhattan in ''Comicbook/{{Watchmen}}'' puts all these guys to shame. [[spoiler:As Jon Osterman, he got disintegrated by radiation, to the point that they had nothing to bury. Somehow his consciousness survived and, in a few months, mastered command of matter to the point that he could remake himself from essentially ''nothing''. Later, he is completely disintegrated ''again'', and is back (and huge) in 5 minutes.]]
-->'''Doctor Manhattan:''' I'm disappointed in you, [[spoiler: Adrian]]. I'm very disappointed. Reassembling myself was the first trick I learned. It didn't kill Osterman. Did you really think it would kill me?
* The comic book character ComicBook/TheSentry has been able to unwillingly and unconsciously regenerate his entire being from nothing.
* Daredevil of ''ComicBook/EarthX'' can do this--including ending up as many copies of himself after being torn apart by a mob. He even makes it into a circus act in which people try every method imaginable to kill him. [[BlessedWithSuck Too bad for him]] he's a DeathSeeker.
* Comicbook/SwampThing once lost an arm, which grew back (for the first time in his book). Later, he met a mindless clone of himself which had grown from the lost arm. During the later Creator/AlanMoore run of ''Comicbook/SwampThing'', he could dissolve his body at will and re-appear from any form of plant life whatsoever, anywhere in the world. (He later got exiled into space with help from ComicBook/LexLuthor, though, but he managed to find a way to return.)
* Modular Man from ''ComicBook/TomStrong'' isn't quite at this level- he is, technically, mortal, and can be killed- but functionally he's identical: if even one of his modules exists, he can use it to make more. And he posted the plans for free download all over the internet...
* Doomsday, [[ComicBook/TheDeathOfSuperman The One Who Killed]] Franchise/{{Superman}}, regenerated from being reduced to a skeleton. Lex Luthor helped by pouring some of Superman's blood on the bones to give him some raw material to work with. It was later revealed in Doomsday's back story that he was created with the ability to die and then evolve an immunity to what ever killed him upon resurrection.
* [[Franchise/GreenLantern Black Lanterns]] are [[ZombieApocalypse zombies]] with power rings that can regenerate them back to full health, even if their entire body is destroyed. The rings themselves are MadeOfIndestructium.
* ComicBook/XMen: Mister Sinister. As an aside, quite apart from this healing factor he has back-up plans in the event that someone does manage to kill him, namely that he secretly experimented on several characters in their childhoods (including Juggernaut, Professor X and Sebastian Shaw) to allow his mind to be transferred to them telepathically while their DNA is overwritten with his. So even if you stop him returning from a single cell, he'll still come back. Not helped by the fact that all three of those characters are quite hard to kill anyway, and one is nigh-invincible.
* In UsefulNotes/{{the Silver Age|of Comic Books}}, Franchise/TheFlash (Barry Allen) was a rare heroic example, as he was able to reconstitute himself from extreme fates such as being ''vaporized'', apparently due to his complete control over his molecules. The one thing he couldn't save himself from, however, was [[ComicBook/CrisisOnInfiniteEarths being converted into energy]] in an epic HeroicSacrifice.
* [[Comicbook/IncredibleHulk Hulk's]] Maestro incarnation was capable of regenerating from dust.
* [[TheJuggernaut Juggernaut]], while never having to regenerate from a single cell, is capable of regenerating from being completely skeletonized...[[NighInvulnerability assuming you can even damage him in the first place.]]
* In the ''Film/{{Godzilla 2014}}'' tie-in comic ''Godzilla: Awakening'', Shinomura's body is composed of thousands of individual cells that will grow into a new Shinomura if left alone.
* In the ''[[ComicBook/UltimateFantasticFour Ultimate Doomsday Trilogy]]'', Ben Grimm manages [[spoiler:to kill The Maker[=/=]Reed Richards... or so he thinks. It turned out that the body Ben destroyed was merely an extra body spawned from a hair-thin tendril from his central mass which is quickly regenerated. When Reed is finally cornered by the Ultimates and his former teammates, he implies that so long as a microscopic bit of him remains his bacterial stack can grow back]].
* ''ComicBook/FiendsOfTheEasternFront'': [[TheRenfield Corporal Cringu]] explains that his master Captain Constanta can resurrect from the smallest leftover. [[spoiler:Despite burning him to ashes, Hans finds out that it still wasn't enough.]]

[[folder:Fan Works]]
* [[spoiler: Dark King Joe Dark]] and [[spoiler: Chaos Alex]] both utilize this trope in ''FanFic/ClashOfTheElements'', but it is stated in-story that the best way to counter their regeneration is to burn their cells faster than they can restore them, which Alex Whiter does [[spoiler: with his Blazing Overlord Fist]].
* The [[BadFuture Dark World]] Mane Six in the ''Fanfic/PonyPOVSeries'' due to their Elements of Chaos (which Discord replaced their hearts with) giving them CompleteImmortality so long as the Elements aren't destroyed or forcibly removed from their body while they're whole. Unusually, the ones that have turned good keep the power. Unfortunately, most of their enemies have the same ability if not better and the one that didn't knew how to deal with it [[spoiler:and had [[ResurrectiveImmortality something nearly as good]]]], so it's not as big of an advantage as it'd otherwise be.
** [[PhysicalGod The Alicorns and Draconequi]] both are capable of surviving and healing from unholy amounts of damage. It would seem nothing short of being vaporized can actually kill one. And even then, their natural forms are spirits that can live on past death, though killing them ''does'' seem to prevent them from just returning to the mortal plane. The only exception was [[spoiler:Discord, who was shattered after being turned to stone. A fail-safe Havoc put in place allowed his spirit to remain in the mortal plane and possess a pony, whom he used his powers on to turn into a clone of his original body]]. Even then, it takes a massive amount of damage or special weapons to actually pull off under most circumstances.
* In ''FanFic/QueenOfBlood'' [[spoiler:Crawler]] is reduced to a fragment of bone which Dragon's scans show to be inert. He's actually alive and regenerates which is ''not'' good for him as he's [[spoiler:[[AndIMustScream floating helplessly in interplanetary space for the next five years]] before crashing into Jupiter and [[RasputinianDeath spending the next few years with his body trying to adapt until the shard gives up]]]].
* The ''WesternAnimation/MyLittlePonyFriendshipIsMagic''/''WebVideo/DragonBallZAbridged'' crossover ''[[https://www.fimfiction.net/story/372472/cell-vs-the-rainbooms-cellgames Cell Vs The Rainbooms #CellGames]]'' does it literally: after her friends were at the wrong end of a CurbStompBattle in the first chapter, Sci-Twi comes to Cell and uses a device of her own invention to degrade his cells, but leaves a single cell intact to study it later-with obvious consequences.
-->“Lucky for me, you left one cell behind.” Cell explained, in a completely calm tone. “It turns out that I can regenerate from just that – who knew?”

[[folder:Films -- Live-Action]]
* One of the more dangerous qualities of ''Film/TheThing1982'' (the shape-shifting BodyHorror one, not the space carrot), provided it has biomass to feed on. The kicker? It only needs a single cell to consume you from the inside out.
* ''Film/{{Species}}'': At one point a single cell is injected with the alien genetic material. It immediately starts dividing and growing, but is killed before it finishes turning into one of the Sil-type monsters. At the end of the movie it's implied that any part of one of the monsters can regenerate into a whole.
* FrankensteinsMonster from ''Film/FrankensteinConquersTheWorld''. In fact, this results in the creation of the two monsters in the sequel, ''Film/WarOfTheGargantuas''.
* This is how the title monster in the B-movie ''Film/{{Reptilicus}}'' is created. A dinosaur tail, found frozen, regenerates into a full dinosaur once it thawed. It then goes on the rampage in Denmark. In the end, it gets put to sleep where they can then KillItWithFire. [[spoiler:Almost. A foot survived destruction, implying that it will regenerate and return again.]]
* In ''Film/TheFifthElement'', the ActionGirl protagonist Leeloo is regenerated from scratch in a rather cool sequence near the beginning of the film. Not to mention the nice FanService. The doctor who restores her practically quotes this trope when explaining the process, saying "A couple of cells are still alive. It's more than I need."
* In the "Sorcerer's Apprentice" segment of ''Disney/{{Fantasia}}'', Mickey Mouse can't stop the enchanted broom from flooding the room with water, so he chops it to bits. Unfortunately, each of those bits turns into a broom - complete with ''buckets already filled with water!'' - ready to continue the job.
* At the end of ''Film/TheSpirit'', it is implied that the Octopus, who has just been blown up all over an alleyway, will be able to regrow himself from a single finger.
* Serleena from ''Film/MenInBlackII'' seems to have this ability.
* In ''Film/GuardiansOfTheGalaxy'', [[PlantPerson Groot]] is blown up from his HeroicSacrifice to protect the team from the BigBad's ship crashing. [[spoiler: Rocket Raccoon takes one of his twigs, which regenerates into a tiny Groot that will grow back to full size, albeit without the original Groot's memories.]]
* In ''Film/RebirthOfMothra3'', King Ghidorah regenerates from a severed tail.
* In the killer fish B-movie, ''Film/DevilFish'', this is one of the eponymous creature's abilities - apparently even one single cell severed from the original creature will grow a new Devil Fish. This is a pretty big problem since the creature is also unstable and designed to disintegrate after a week or so, which will then reform into dozens if not hundreds of new Devil Fish.
* In ''Film/ShinGodzilla'', the scientists note that the little chunks of Godzilla's flesh that broke off are slowly growing.

* The immortals of the Kage Baker ''[[Literature/TheCompanyNovels Company]]'' series of books, well...it takes a LOT of destruction to get any of them to the point where they can't be brought back.
* The traditional way to kill vampires in western literature involves staking, beheading, then burying at a crossroad at midnight with garlic in their mouths. They can still come back. Usually, the only way to truly kill them is to burn the body and scatter the ashes to prevent them from reforming, usually into moving water.
** ''Literature/{{Discworld}}'' jokes about the various and complicated methods of killing vampires by having vampires from different areas have different weaknesses. Furthermore, all vampires on the Disc can be brought back to life with a drop of blood - even if they were burnt to ashes. In fact, one vampire is a photographer for Ankh-Morporkh's newspaper and gets turned to ash every time he uses the flash. He carries around blood in a breakable vial so he instantly gets revived when this happens. Consequentially, one group of [[FullyEmbracedFiend particularly bad vampires]] is threatened with having their ashes thrown over the Rim into outer space.
* Creator/MargaretWeis and Creator/TracyHickman had monsters that could do this in ''Literature/TheDeathGateCycle''. You had to stab a "chaodyn" in the heart, because if not they would heal and the blood that had dripped out of the wound would spawn a second chaodyn. (Killing them without spilling blood worked too.)
* BlessedWithSuck example from Creator/OrsonScottCard: ''Literature/APlanetCalledTreason''. One of the families exiled to an isolated world has genetically-engineered themselves to a state in which they can regenerate organs, so that they can sell them to eventually buy their way home. Occasionally a mutant like the protagonist appears whose regenerative abilities approach this level -- but he also grows extraneous body parts that eventually cripple, then kill him. At one point, his guts are ripped out, producing [[WildChild a feral copy.]]
* Twice, by two different characters (both [[ResurrectiveImmortality Perpetuals]], though) in ''Literature/HorusHeresy'':
** Oll Parsson is hit by piece of a spaceship crashing on Calth's surface, but is fine and good after a few hours' blackout.
** Vulkan is immolated by falling all the way through Macragge's atmosphere when his teleporter doesn't work quite as planned and wakes up on planet's surface, although the experience makes him go crazy.
* The book ''[[Film/JasonX Jason X: The Experiment]]'' has Jason Voorhees coming back after being reduced to little more than a hunk of flesh due to being incinerated during atmospheric reentry. It takes him a couple years (even with help from {{nanomachines}}) though.
* The Literature/{{Animorphs}} frequently make use of the morphing power's healing properties. Their fights often go like this: Attack; get torn to shreds while decimating the enemy's defenses; de- and remorph; carry out the mission. Rachel in particular seems to lose and regrow limbs on a regular basis.
** Their regeneration ability becomes a major plot point in one book where Rachel morphs into a starfish and gets cut in half. She returns to her human form, but so does her other half, creating split personality Rachels, a decent, kind-hearted girl, and a total ruthless bitch.
* Creator/GregBear's ''Literature/BloodMusic'' takes a different spin on this. [[spoiler: The noocytes are able to encode the squishy chemical versions of people into molecular memories based on DNA/RNA. The noocytes can rebuild and upload the original person - or an amalgam of anyone who wants to participate - back into a squishy flesh body should they so wish. After encoding and absorbing almost all biomass on North America, there are uncountable replicas of everyone to the point that there is no possible way to erase every copy.]]
* One of the ''Series/StarTrekTheNextGeneration'' novels mentioned a race that fought a brief war with the Federation over this trope. Because they were effectively immortal, one of their more revered ways of learning things was by dying, because you usually at least learn "That was a bad idea." Because they thought every race had the same trait, they didn't realize that they weren't doing the Federation any favors by killing them.
* In ''Literature/OnStrangerTides'' by Creator/TimPowers, [[spoiler:anyone who drank from and then shed blood near the Fountain of Youth]] could regenerate from even the smallest part of himself, even a drop of blood, so long as it fell into the ocean.
* The Radiants of ''Literature/TheStormlightArchive'' can survive just about any injury if they're holding enough of the titular Light.
* Alluded to on a factional level in ''Literature/TheCulture''. It's said that if even one GSV escapes a conflict, it could singlehandedly rebuild the eponymous faction.
* The main characters in ''Literature/EdenGreen'' are infected with a needle symbiote that can resurrect them from any death, including complete immolation and being torn down to tiny pieces.
* Crawler of ''Literature/{{Worm}}'' can instantaneously recover from any injury, even if almost all his bodymass- including his brain- is destroyed, and [[AdaptiveAbility becomes immune to whatever injured him to boot]]. [[spoiler:He's only killed by a weapon that [[TakenForGranite transforms his body into silicon]], and when [[MadScientist Bonesaw]] makes clones him, Dragon resorts to nanotech weapons that obliterate his entire body at once.]]
* The title [[BlobMonster creature]] in ''Literature/TheClone'' begins its life at a microscopic level in a sewer catch basin. It grows steadily bigger by feeding on all the bacteria and fungi lining the basin, allowing it become large enough to leave the basin and expand through the sewer, up through drains and pipes and into the [[UsefulNotes/{{Chicago}} city]].

[[folder:Live-Action TV]]
* ''Series/KolchakTheNightStalker'' (1974) episode "Primal Scream". An ancient cell sample discovered in the Arctic regenerates into a murderous ape man.
* Grim reapers in ''Series/DeadLikeMe'' are effectively impossible to kill, being already dead. In the movie the cast try to kill a renegade reaper by shooting, drowning, and finally dismemberment followed by cremation and launching the ashes into space.
* Jack King in ''Series/{{Reaper}}'' could form a new self from just a hand. Possibly less, we never saw him try.
* The Replicators in ''Series/StargateSG1'' come close. It only takes one active Replicator to make an entire swarm. Fortunately, they are limited by local resources, and there need to be at least enough active blocks to form a working entity. They can't actually regenerate from a single cell.
* The ''Series/DoctorWho'' villain [[Recap/DoctorWhoS14E2TheHandOfFear Eldrad]] first appeared as a fossilized hand, then having absorbed some nuclear radiation, turned into a walking hand. Eventually it regenerated into an entire person.
** In a very similar vein, there was a time when the Doctor himself had a previously-severed hand put away somewhere. Then, when Ten tried to stop his own regeneration, he shunted the regeneration energy into said severed hand. The hand then grew a not-so-clone of Ten (he was more Human than Time Lord). It should be noted that the Doctor himself averts the trope. While he ''can'' regenerate from fatal damage, there are known limits to this ability and there are a number of ways to outright kill a Time Lord.
* Captain Jack in ''Series/{{Torchwood}}'' is not invincible, but ''always'' comes back to life after being killed, no matter how severe the damage. Even when in ''[[Series/TorchwoodChildrenOfEarth Children of Earth]]'' he is [[spoiler:torn to shreds by a bomb planted ''inside his chest'', and the only thing remaining of him is an arm, a shoulder, and part of his head, he regenerates fully within a few hours. [[AndIMustScream He is conscious for most of it]] and it is ''very'' painful]].
* ''Franchise/UltraSeries'' examples:
** Salamandoras from ''Series/UltramanEighty'' goes by the BossSubtitles of "Regeneration Monster", but in his original appearance he had to be regenerated by the Gorgonians who controlled him. In ''Series/UltramanMebius'', the regeneration was remade into a natural ability performed via the AchillesHeel on his throat that must be damaged in order to destroy the monster permanently.
** Gyeron from ''Series/UltraSeven'', as Ultra Garrison found out after they successfully blew up the mutant alien. When Gyeron reappeared in an episode of ''Series/UltramanGeed'', this was his primary trait, as the monster constantly regenerated itself over the course of a day to reappear at the exact time and location until Riku and his friends found out they could neutralize it with [[KillItWithIce freezing temperatures]].
** The [[MechaMooks Imperisers]][[note]][[SpellMyNameWithAnS Imperizers, Inpelaizers, Imperializers, etc]][[/note]] from ''Series/UltramanMebius'' who have to have their entire body vaporized to kill them, otherwise, they would regenerate, even from having their upper half totally destroyed. Later on in the finale, this is toned down to having to destroy a certain part of their body to prevent complete regeneration, but the damn things are still {{Nigh Invulnerab|ility}}le beforehand. Worst part, the Imperisers are the BigBad's ''Mass Produced'' '''[[BossInMooksClothing Minions]]'''.
** [[RodentsOfUnusualSize Nosferu]] from ''Series/UltramanNexus'' proved to be a serious pain in the ass for the Night Raiders because of this. Like Salamandoras, he possesses a special organ[=/=]AchillesHeel for this, but unlike the others above, had to slowly grow back to its original {{kaiju}} size by ravenously eating. Not surprisingly, Nosferu took the longest to finally kill out of all the Space Beasts.
* ''Franchise/SuperSentai''
** In Series/UchuSentaiKyuranger, as long as a single piece of [[EverythingsSquishierWithCephalopods Madako]] survives her destruction, the villainess is capable of completely regenerating again and again.
** ''Series/GoGoSentaiBoukenger'': The helmet of Creator King Ryuuwon is actually a ClingyMacGuffin that granted Ryuuwon immortality as a [[LizardFolk humanoid reptile]], as well as the power to survive falling off a high cliff, getting blown up while piloting his [[HumongousMecha dinosaur-mechs]] two, maybe three times, and suicide. However, this power fails Ryuuwon when Bouken Red destroys it during the two's final duel, causing Ryuuwon to revert back to his original human form. [[Series/KaizokuSentaiGokaiger He gets better]].
* ''Series/{{Space 1999}}'' episode "End of Eternity" features Balor, who is imprisoned forever on an asteroid by his immortal race. At the start of the episode he quickly recovers from horrific explosion and rockfall injuries. At the end, he's blown out onto the Lunar surface (or into space - the episode glosses over this). The question of what happens to a From A Single Cell individual left in a vacuum is never addressed.
* The Supersoldiers in ''Series/TheXFiles''. Even after being crushed and mashed to pieces, they can regenerate from a single vertebra.
* ComicBook/VandalSavage in ''Series/LegendsOfTomorrow'' fits this. Even after being completely obliterated by [[Series/TheFlash2014 the Flash]] and [[Series/{{Arrow}} Green Arrow]], he still regenerates and conquers the world in the distant future, setting the events of the series in motion. Given that Merlyn collected his ashes after Savage was incinerated by the Staff of Horus and said "You owe me.", he probably knew this was going to happen. [[spoiler:The only way to kill Savage for good is for Kendra/Chay-Ara to stab him with the Amon Dagger. Alternatively, Savage's immortality is negated by his presence near one of the Thanagarian meteorites, so he can be killed by anyone.]]

[[folder:Myths & Religion]]
* There's at least one folktale where, when an evil wizard was burnt at the stake, [[OneToMillionToOne countless birds and bugs burst forth from the fire]], and all of them had to be caught and killed, for if just a single one escaped it would reform into the slain wizard.
* A similar version appears in one of the more [[ThereIsNoKillLikeOverkill thorough]] methods of disposing of vampires. When you burn the body after staking it, chopping off its head and stuffing its mouth full of holy wafers, you have to drive back any rats or beetles that scurry out of the fire. It's not entirely clear what would happen if it did get away though.
* In Myth/HinduMythology, the demon Raktabij could birth a new form from every drop of blood. Kali solved this by having the demons strangled. Part of the origin myth of the Thuggee cult. An alternative version is she cut off his head, then drank all the blood that flowed out.
* The Hydra in Myth/GreekMythology. Cut off one head and ''two'' grow back unless cauterized with fire.

[[folder:Tabletop Games]]
* ''TabletopGame/DungeonsAndDragons'':
** Any creature with regeneration works this way unless you take its HitPoints to -10 with whatever form of damage it can't regenerate (that's when a creature is officially considered Killed -- -1 to -9 HP is only considered Dying). A joke ''D&D'' item exists called "Troll in a Can" that uses this trope to turn a chunk of trollflesh into self-regenerating field rations. [[spoiler:Wizards of the Coast ruled that eating a troll will eventually cause a new troll to ''grow inside you and EXPLODE OUT OF YOUR BODY''. (Unless it's well done on a bonfire, since trolls do not regenerate fire damage and can be safely killed by it.)]]
** The Tarrasque has this ability. The only way to defeat it is to beat it into unconsciousness and then use the most powerful spell in the game to make sure it doesn't wake up. (Good thing it sleeps 99% of the time.) And as of Fourth Edition, the Monster Manual implies that the only real way to kill the Tarrasque for good is to send it into space. Reducing its HP to 0 just sends it back to slumber beneath the earth. Second Edition required the Tarrasque to be reduced to -50 hit points, requiring the use of +1 or better magical weapons, then a Wish spell or equivalent to be used wherein you wished for the Tarrasque to never return. Depending on your DM at the time, sending it into space may be a lot easier.
** In the ''TabletopGame/{{Ravenloft}}'' campaign, Dr. Victor Mordenheim, the MadScientist responsible for the blasphemous experiment that created Adam, the Lord of Lamordia, has this ability, whether he wants it or not. Even though he is not the true Lord of the domain, he is cursed to share Adam's IronicHell, and cannot die while Adam lives. Thus, he can't be killed. In fact, he would even survive if not a single cell were left; if that happened, his soul would become bound to a recently-dead corpse that would regenerate and turn into a duplicate of his old body.
* ''TabletopGame/ChroniclesOfDarkness'':
** The Hosts of ''TabletopGame/WerewolfTheForsaken''. These are bizarre hybrid spirit creatures (most commonly the [[GiantSpider Azlu]] and the [[RodentsOfUnusualSize Beshilu]]) who are able to either take on vaguely human forms or [[BodyHorror hide inside human skins]]. If a Host is destroyed, its body will shatter into dozens or hundreds of its animal form (which will look like mundane animals), one of which contains its soul. They all need to be destroyed to be safe or else they will eventually consume enough to regrow into their monstrous forms (and usually be pissed at whatever killed them).
** In ''[[TabletopGame/NewWorldOfDarkness World of Darkness: Immortals]]'', we have the Purified, who have this as one of their main abilities. You see, they've turned their souls into spirits, and like the Hosts above, just killing one's body simply sends his mind to the [[SpiritWorld Shadow]], where they can rebuild it even if it was completely destroyed. They're a perfectly viable character option (far more so than the {{blood bath}}ers and the [[BodySurf body thieves]]), and this ability is mitigated by the fact that the Spirit World is rather dangerous. That still means a halfway competent Purified is going to be alive for a very long time (this is a book called ''Immortals'' after all), but it's something of a weakness.
** The Abmortals from ''TabletopGame/GeistTheSinEaters'' are people who found ways (usually [[PoweredByAForsakenChild very amoral ones]]) to make themselves immortals. They all have a single AchillesHeel allowing you to kill them, but this aside, they are this trope: you could cut them to pieces and burn their remains, they would ''still'' eventually regenerate and come back.
* The Ananasi and Kumo (werespiders) in ''TabletopGame/WerewolfTheApocalypse'' could break into swarms of normal-sized spiders (called the Crawlerling form). If a single spider from the swarm survived, it could eventually hunt enough to increase its mass to the point that it could resume human form. (Unfortunately, the Ananasi in such a situation would probably lose almost his entire memory...)
* In ''TabletopGame/{{GURPS}}'', this is the 100-point level of Unkillable. For just 50 points more, you don't even need that one cell.
* While the Necrons of ''TabletopGame/{{Warhammer 40000}}'' don't have cells, being automatons, they fit the spirit of this trope, able to regenerate or be repaired from any damage whatsoever. Well, at least originally; newer versions seem to have {{Nerf}}ed that ability significantly.
** [[HordeOfAlienLocusts Tyranids]] are this trope on an interstellar scale, when considering that their Hive Fleets and HiveMind are really just one big body. If even one vessel manages to survive and reaches an ill-defended planet or three, they can use the biomass to rebuild the entire fleet.
** Da Orcs on a species scale, since they reproduce by [[PlantAliens fungal spores]], all they need is a single spore left over from battle and [[KillItWithFIre untouched by cleansing flame]] to sow the seeds of a new invasion.
** The ExpandedUniverse brings us the Halo artifacts, which are completely disturbing.
** The latest incarnation of the Dark Eldar Codex indicates that [[MadScientist Haemonculi]] can regrow people from small amounts of flesh, leading to many Dark Eldar leaving a bit of skin or a finger in a Haemonculus' care when heading out on raids to act as insurance should they perish.
** Also, [[WhoWantsToLiveForever the Perpetuals]]. They don't even need an entire, intact cell; they can regenerate from ''complete and total atomization''. The only Perpetual to have canonically died is Ollanius Pius, on account of Horus' CessationOfExistence attack, but even that much has the fandom going back and forth on the HesJustHiding option.
* ''TabletopGame/MagicTheGathering'' has [[http://gatherer.wizards.com/pages/card/Details.aspx?multiverseid=106473 Squee]], the goblin who, as both [[OurVampiresAreDifferent Crovax]] and [[EvilSorcerer Ertai]] learned, could never stay dead. Ever.
** On a larger scale, we have the Phyrexians. As long as a single drop of glistening oil remains, they can be reborn continuously, forever.
* ''TabletopGame/{{Exalted}}'' has Chimeras, Lunar Exalted who have gone bat-shit insane, that can learn this. The Knack is called "Perfect Regeneration", and also solves the question about "which part regenerates"; the Chimera's spirit will always occupy the largest remaining part. This lends itself to some interesting ideas about how you could permanently kill it with relatively mundane methods, but since we're talking about an [[PersonOfMassDestruction Essence 6]] AxCrazy shape-shifter-slash-titan-killing-weapon-gone-rogue, it might just be easier to pop a Total Annihilation on it...
** And one of the Lunar Exalted's most characteristic traits is their ability to tank obscene amounts of damage, so you had better be ready to pop another half-dozen different WMD-level spells, just to be sure - they also excel at adapting, so just spamming one is unlikely to work too good. And it might still take cover in an otherwise inaccessible pocket dimension, or space-warp into the Wyld, or... You get the idea.

[[folder:Video Games]]
* ''VideoGame/{{Xenosaga}}'''s Albedo Piazolla may be the single most indestructible example on this page. It takes a CosmicEntity to kill him permanently, and even then, ''[[BackFromTheDead he comes back.]]'' The third game ends with him asleep in his twin brother's subconscious mind, with the implication that this might not be a permanent arrangement...
* One of the hardest bosses in ''VideoGame/{{Xenogears}}'' is Miang Hawwa's Omnigear Opiomorph, which had been transfigured from OrganicTechnology into essentially GreyGoo by the game's BigBad Krelian. After the party beats it, it promptly snaps back up to fighting position like nothing even happened to it. Cue Miang gloating about how the entire Gear can restore itself from a single atom if need be.
* ''VideoGame/{{Touhou}}'''s Fujiwara no Mokou and Kaguya Houraisan. The Hourai Elixir they drank granted them immortality and the ability to come back to life even if their bodies were completely destroyed, and beyond that. Yuyuko has the ability to kill ''anything'' by simply inviting it to its death, and once attempted to use it on Mokou. She couldn't even find her death. Turns out the Hourai Elixir simply banishes their death at every point in their timeline, ensuring they can never die ''no matter what''. Even if they could get someone to kill them before drank the Elixir, ''it would fail'' - their deaths would have been retroactively banished. ''It's just that good at averting death''.
** Marisa, being Marisa, lampshades it by asking what every one of us has always wondered: if we split either in half, which half will regenerate?
** Fairies have a similar level of regeneration ability in the series, being somewhere between this and FightingAShadow. However, they are idiot {{mooks}} subject to TheFogOfAges.
* Jenova from ''VideoGame/FinalFantasyVII'' can apparently regenerate indefinitely so long as some cells still exist.
** Which is what provided the retroactive SequelHook: Cloud (and others) are infected with Jenova cells, and thus Jenova [[spoiler:and Sephiroth]] are not truly dead, but, in fact, possibly more powerful than ever.
* Also from Final Fantasy, [[BigBad Exdeath]] of ''VideoGame/FinalFantasyV'' once rebuilt himself ''from a single splinter''.
* Roa from ''VisualNovel/{{Tsukihime}}'' can be like this, but only when the conditions are absolutely right (midnight during a full moon, [[spoiler:as Arcueid found to her chagrin, when he regenerated from ''his ankles up'']]).
** Arcueid herself is able to construct an entirely new body after being sliced into seventeen pieces by Shiki near the beginning of the game.
** It is explained at some point that in case of most powerful beings (like Shinso and Dead Apostle Ancestors) the wounds do not regenerate by normal means (i.e. cell division cranked UpToEleven) but rather by reversing the flow of time around the missing body part (or even missing body, for the most powerful of them returning from the state of complete non-existence is just as simple) effectively making the wound to never existed. Of course most of those creatures also have abnormal HealingFactor just in case someone attacks them with means [[note]]like Conceptual Weapons[[/note]] that prevent recovery by time reversal.
* The Bacterians from ''VideoGame/{{Gradius}}'' work like this. Every time you defeat them, they regenerate and come back stronger.
* At the end of ''VideoGame/{{Prototype}}'', [[spoiler:Alex Mercer saved New York from being nuked by flying the nuke out over the ocean. Unfortunately, he didn't escape the blast, and a few mangled fragments of him wind up in Manhattan. A crow eats the pieces; which then eat the crow. Alex rebuilds himself from the inside out]].
* ''Franchise/{{Metroid}}'':
** ''Every single enemy'' in ''Videogame/MetroidFusion'' works this way. Since they're all X-Parasites mimicking various creatures, they revert to the cellular form when defeated. The only way to kill that form is to absorb it (which only Samus, or a metroid, can do). If the cell form isn't absorbed, it recreates its body or infects the killer. Some can even spawn more cell forms, creating even more monsters.
** Ridley also seems to have this, as his entire body routinely explodes, though ''Videogame/SuperMetroid'' was the canonical death of the original Ridley. A clone was made in ''VideoGame/MetroidOtherM'', which the X Parasites infected in ''Fusion''.
** The Metroid Prime [[spoiler:AKA Dark Samus]] has survived everything up to and including [[spoiler:being vaporized and then caught in the destruction of an alternate dimension immediately afterward]]. The [[HundredPercentCompletion 100% completion]] endings of the first two games of the ''[[Videogame/MetroidPrime Prime trilogy]]'' show the player that, yep, it's still alive and kicking.
* The Flood of ''Franchise/{{Halo}}'' are this trope on a much larger scale. From a single spore the Flood can rise again, and even if its [[EldritchAbomination Gravemind]] is destroyed, its [[HiveMind communal memory]] remains.
* ''VideoGame/{{Terraria}}'': Once Hardmode hits, the Corruption and the Hallow spread constantly. As long as one block of Ebonstone or Pearlstone exists within 3 blocks of a block of grass or stone, they will continue to spread. Additionally, destroying a Demon/Crimson Altar to spawn the rare ores will create a block of Corruption/Crimson somewhere in the world, meaning that it can literally grow from a single cell.
* In the Powder Toy, most forms of 'exploding' life will regenerate no matter what you do.
* ''Videogame/ContraHardCorps'' has this being one of the main plot points for the game and main motivation for the big bad. Just a single cell from Red Falcon is enough to cause devastation on a planetary scale. In most endings if the Alien Cell is grown it can easily: turn into back into a hive monstrosity, or re-purposed as a biological bomb; or be used as fuel for a giant doomsday weapon. In the one ending it isn't released it's fused with the big bad who turns into massive alien monstrosity himself.
* In ''Videogame/{{Boktai}}'', the [[NamesToRunAwayFromReallyFast Count of Groundsoaking Blood]] can come back from the dead as long as one of his bats is still alive.

[[folder:Web Comics]]
* Xykon from ''Webcomic/TheOrderOfTheStick'' is able to regenerate from any injury as long as his SoulJar still exists. After his first (and so far only) defeat, he was notably ably to regenerate his whole body from essentially nothing. This is a standard ability of all Liches in ''D&D''.
* Schlock from ''Webcomic/SchlockMercenary'' kind of does it [[http://www.schlockmercenary.com/d/20041019.html here]]. When 80% of his body mass is incinerated in an explosion, the remaining mass is able to re-assemble into a sapient individual- but Schlock loses most of his mind in the process, (it's spread throughout his body) and regresses to a child-like state. It's implied that while his memories are gone for good, in time he'll eventually just grow up into an adult again. Or he would if he hadn't [[spoiler:{{Time Travel}}ed back into the past and merged with his alternate-universe counterpart]]. Thereby also answering the question of what happens if he gets split in half.
* In ''Webcomic/ProblemSleuth'', Demonhead Mobster Kingpin's 2nd form has 3 health bars, all regenerating extremely quickly. However, if you knock out a health bar, it's gone for good. His 3rd form has enough bars to, from the center of the universe, physically break into hell, and he could regenerate entire bars just about whenever he wanted to.
* Ed from ''{{Webcomic/Megatokyo}}''.
* In ''Webcomic/ElGoonishShive'', the Goo can [[http://www.egscomics.com/?date=2002-11-09 regenerate its amorphous body]] if its demon nuclei survives.
* In ''Webcomic/{{Archipelago}}'', [[spoiler:the mechanical soul-stealing arm [[ManInTheMachine that is currently home to Captain Snow's soul]]]] can regenerate from a single chip of its material.
* In ''{{Webcomic/Nimona}}'', it's pretty heavily implied that this is the root of [[spoiler: both Nimona's Shapeshifting powers and HealingFactor. Every time Nimona transforms, all of her cells are destroyed and reformed. It's how she can resurrect and split into two bodies]].

[[folder:Web Original]]
* The Wiki/SCPFoundation's [[http://www.scp-wiki.net/scp-682 SCP-682]] is seemingly unkillable, though it's not for lack of trying on the Foundation's part. [[http://www.scp-wiki.net/experiment-log-t-98816-oc108-682 Various attempts]] at destroying it have reduced it to as little as '''1%''' of its original body mass before it adapts and regenerates.
* [[spoiler: Darkwing, as a parody of the T-1000,]] in ''WebAnimation/{{Ducktalez}} 6''.
* As a result of meddling by a dark god, the trolls of ''WebVideo/TalesFromMyDDCampaign'' can regrow from nothing more than their jawbone. Since the jawbone itself cannot be destroyed by any known force whatsoever, this renders trolls utterly unkillable.
* ''WebOriginal/{{Mortasheen}}'' zombies work this way, given their absurdly powerful healing factor and the fact that their consciousness is spread out all over their body. Downplayed in the sense that, depending on what exactly happened to them, they may not regenerate correctly or even lose their intelligence.

[[folder:Western Animation]]
* Amazo in ''WesternAnimation/JusticeLeague'' and ''Justice League Unlimited'' is made of Nanomachines, and thus he can reform from any injury that doesn't completely destroy him. However, this was subverted at first because he only gained the ability to do this after he copied the Martian Manhunter. Before that, a small explosive in his brain really would have killed him. This trope was double-subverted in a later episode. In an EnemyMine assault against Amazo, Lex Luthor and the League use the robot's blueprints to build a weapon capable of disabling its nanomachines. However, it's soon revealed that ''Amazo'' knows about this limitation, and had evolved itself beyond the nanomachines' tech threshold, rendering the weapon useless.
* ''[[WesternAnimation/TheSimpsons The Itchy and Scratchy]]'' parody of ''The Sorcerer's Apprentice'' has thousands of Itchys regenerating after Scratchy chops him up into fine dust. Unfortunately for Scratchy, they regenerated ''after'' he inhaled some of that dust.
* Bushroot in ''WesternAnimation/DarkwingDuck'', as a plant/duck/thing, can regenerate even if there are only tiny vines left of him. Through the whole series, he's been mulched at least twice.
* This once happened to General Skarr on ''WesternAnimation/TheGrimAdventuresOfBillyAndMandy'' when he became a plant like being after coming in contact with Grim's scythe. At the end he is blown through the air by an exploding lawn mower and is chopped to pieces by a helicopter and we see him slowly regenerate later.
* In the ''WesternAnimation/{{SpongeBob SquarePants}}'' episode "Franken Doodle", said doodle recreates its body by redrawing itself with a magic pencil.
* ''WesternAnimation/DannyPhantom'' has two dangerous enemies with this kind of power: Undergrowth and Nocturne. Apart from instant recovery from Danny's attacks, this trait is made apparent when Undergrowth managed to (offscreen) completely regrow his body after it was blown to nothing but a weed and Nocturne was able to pull himself back together after Danny froze him solid and shattered him.
* The BigBad of ''WesternAnimation/GeneratorRex'' Van Kleiss is able to rebuild his entire body using the nanite-infused soil of his homeland. He did this near the end of the ''first episode'' after Rex smashed him to pieces. After being brought BackFromTheDead, he can no longer do this.
* In the first animated ''WesternAnimation/StarWarsCloneWars'' series we've got alien bounty hunter Durge who has incredible healing powers. We see him recover from been cut into half, and later in that series he got [[LudicrousGibs blasted into a gooey mess]] via the Force by Obi-Wan. The schocker: Durge ''still survived'' this in [[Franchise/StarWarsLegends other works]]! He was finally KilledOffForReal by Anakin, who [[HurlItIntoTheSun hurled him into a sun]].
* The [[http://www.youtube.com/watch?v=37lf4n6lxX0 R.E.G.I.S]] [[WesternAnimation/MegasXLR Mk V]]. [[spoiler: If there is sunlight and a small piece of it remains, it will reconstitute itself.]]
* In ''WesternAnimation/ThePenguinsOfMadagascar'', the penguins clone a whole dodo out of a single feather. When said dodo dies minutes later because [[TooDumbToLive he's stupidly reckless]], they reclone him from one remaining feather, and he acts as if nothing has happened. [[RunningGag This gets repeated all throughout the episode.]]
* ''WesternAnimation/{{Ben 10}}''
** One of his original 10 forms, Ghostfreak, turns out to have this ability. Unfortunately, this means [[spoiler: the mind of the original alien whose DNA sample is in the Omnitrix is present within that sample and capable of restoring himself. And he's '''not''' a good guy]].
** Gluto in the movie, ''[[TheMovie Secret of the Omnitrix]]'' is one giant blob of living gel with three eyes. [[spoiler: He saves Gwen's life by blocking a plasma gun, and for a long time, everyone thinks he's gone for good. But at the end, it turned out that the residue on Gwen's clothes gave him enough resources to regenerate from this level, prompting Tetrax Shard to say, "Who knew?"]]
* The Gems of ''WesternAnimation/StevenUniverse'' are able to regenerate from any fatal injury as long as their [[HeartDrive Gem]] is intact and unharmed. Interestingly, even if an attack does not destroy their body, any would-be fatal attack has them [[NoBodyLeftBehind explode in a cloud of smoke]]- leaving only the Gem, which recreates the entire body. Any damage to the gem, however, can prove fatal, even if the rest of the body isn't harmed. The full Gems' bodies are HardLight projections created by the gems which are their true selves. The titular character cannot regenerate like they can since he's a HalfHumanHybrid with an organic human body.
* ''WesternAnimation/SamuraiJack'': This applies to Aku, the main villain, who is basically malicious darkness empowered with magic and sentience. He's immortal in all respects; normal weapons are less effective than bug bites, and he can even absorb and reflect them. The eponymous protagonist's magic sword, forged from pure righteousness, is the only thing that can destroy him apart from the gods that forged said sword. And even then, while every strike burns part of Aku away, he's fully capable of regenerating from the sword's blows if given enough time, and if even a fist-sized amount of darkness remains, he can use it to shape-shift into a form that will let him escape, which [[VillainExitStageLeft he always does.]] [[spoiler:Right down to the finale, when Jack pursues the last fragment of Aku and stabs him as he runs away, finally destroying him.]]
* ''WesternAnimation/TeenTitansTroubleInTokyo'': All villains under Brushogun can regenerate from any injury in a matter of seconds, from losing a limb to a hole in the stomach. Brute force seems to be capable of killing them, however. [[spoiler:This is due to them being made entirely of ink, meaning that [[KillItWithWater water is fatal to them]].]]

[[folder:Real Life]]
* Medical Science's current obsession: Stem Cells. They are totipotent, this means they can potentially literally regenerate into any organ cell of choosing, provided the right DNA and resources. Unfortunately, the most versatile and abundant totipotent cells are embryonic; most commonly found at the start of an organism's development before mitosis gets too far under way. For example, prior to a certain point, splitting the developing zygote apart results in identical twins. This is why embryonic stem cell research has a negative public reputation as PoweredByAForsakenChild, though efforts to produce "ethical" stem cells from adults such as those found in the bone marrow are underway yet difficult.
** Sponges contain totipotent cells throughout their bodies when mature, potentially giving them the full version of this trope.
* Nematodes. Not only can they regenerate from a single cell, they can ''eat'' themselves till being reduced to one cell if they don't find food, and then regenerate from that single cell left.
* Cancer. If there's even just a few cancerous cells left in an individual, they'll continue to rampantly grow and divide and continue the disease. This is why metastasized cancers are so dangerous, it's ''extremely'' difficult to ensure that all the abnormal cells have been destroyed or removed, and that there aren't any more floating around in circulation somewhere.
** Most notably the [[TheImmortalLifeOfHenriettaLacks Hela]] cells, the first immortal human cell line. They were taken from the cervical tumour of a woman named Henrietta Lacks in 1951 and they're still going. They will also invade and take over any other cells you happen to have growing about the lab - they've done millions of USD worth of damage that way, but it's sort of balanced out by also being responsible for every significant medical discovery in the past sixty years.
* Sea squirts can ''literally'' regenerate from a single blood cell.
* Some species of flatworms and starfish have impressive regenerative abilities, and although they can't grow back from a single cell in isolation, a single individual can survive being cut in half and both halves can independently develop into complete, separate individuals.
** To expand on "single cell in isolation," a flatworm was [[http://blogs.discovermagazine.com/notrocketscience/2011/05/12/an-entire-flatworm-regenerated-from-a-single-adult-cell/#.WXnxVsd97IW exposed to lethal radiation]], crippling its regenerative capabilities and giving it a few weeks to live at best. Then a single donor cell from a different adult worm was implanted in the dying specimen's tail. Two weeks later, an entire healthy adult resulted--its eyes, skin, and organs genetically identical to the donor's despite being grafted onto a dying body. So a single cell ''can'' regenerate an entire flatworm, if said cell has a scaffold on which to grow (the dying adult).
* A few examples from the plant kingdom -- Cultivars are specific clones of certain plants (such as a Fuji Apple, or a Red Dragon Venus Flytrap). You can't grow these by just making seed and hoping the new plant is identical to the parent -- you have to cut off a piece and force the plant to spit out new roots.
** Another plant example is Micropropagation -- that is, taking a single cell of a host plant, putting it into some special goo (essentially extremely sugary jelly), and letting the cell clone itself a few thousand times, all through a process called Tissue Culture. It's difficult to do, being extremely expensive and time consuming... [[http://www.kitchenculturekit.com/ At least it was; nowadays you can do it in your kitchen.]] Isn't science grand?
** Not to mention the innumerable weeds/invasive plants that just ''excel'' at that asexual propagation stuff. Any plant cell from an asexually-reproducing plant has the potential to become a new plant. Many a gardener have probably screamed WhyWontYouDie whilst uprooting creeping charlie on their hands and knees.
** [[http://en.wikipedia.org/wiki/Caulerpa Caulerpa]] is an extreme example. It's normally a seaweed (technically a single-celled algae, making it a literal example of the trope) native to the Caribbean and a few other tropical seas. However a combination of a mutated variety capable of surviving in subtropical and temperate waters, a natural toxicity and the ability to grow back into a full plant from the smallest fragments has turned it into one of the most [[http://cisr.ucr.edu/caulerpa_taxifolia.html dangerously invasive aquatic species]] [[http://www.pbs.org/wgbh/nova/algae/ on the planet.]] Because of its incredible regenerative ability, the only effective way found so far to combat a Caulerpa outbreak is to [[ItsTheOnlyWayToBeSure sterilize the entire outbreak area of all life]] and let the native life recolonize the resulting aquatic desert.
* [[http://www.seaonscreen.org/vleet/content/eng/sacculina-carcini.htm Sacculini carcini]] is a hellish parasite that combines properties of the Alien and the Puppet Masters or the [[Series/StargateSG1 Goa'uld]]. Its larval form attaches to a crab and injects just a few cells, which grow into a sluglike thing that lives in the crab's abdomen and grows a set of tendrils throughout the crab's body, including into its eyes. It controls the crab's behavior also, making it eat constantly to feed the parasite and making the crab care for the parasite's eggs. In a female it seems to be activating maternal behaviors already there, but ''male'' crabs take on the same behaviors when infected.
* All single-celled organisms can technically do this, but it takes away the point when it was a single cell to begin with.