A villain annihilates an entire people and their culture to achieve some goal, but only has an incomplete success and the resulting incompleteness comes back to bite them in the ass in the form of [[SoleSurvivor the one guy or small group of individuals who survived the massacre.]]

It often involves a prophecy, and this is the villains' attempt to "ScrewDestiny." [[SelfFulfillingProphecy For all the good it does them]].

This typically means murdering hundreds of people to kill a single child, who will inevitably escape -- see NiceJobBreakingItHerod. Sometimes, the evil overlord might [[KarmaHoudini live out his life successfully]], but his descendants [[SinsOfOurFathers pay the price]].

Expect the survivor to benefit from WhatMeasureIsANonUnique, using his heritage and tragedy to fuel the coming RoaringRampageOfRevenge (or the even more tragic CycleOfRevenge). SisterTrope to NiceJobBreakingItHerod, with which it can overlap when the motivation behind the Genocide is finding and killing particular individuals.

It is sometimes called the "Dandelion of Doom" or "Dandelion effect," per the expression: "If you kick a dandelion, you spread its seeds." Just as this is an ineffective way to remove weeds from a lawn, it is an ineffective measure to remove potential threats to one's rule.

SisterTrope to NiceJobBreakingItHerod, with which it can overlap. The primary difference is that this trope only requires the villain to wipe out a group of people to achieve some goal, with the survivors subsequently trying to get revenge on him. The Herod approach requires foreknowledge on the villain's part (whether through prophecy or time travel) that someone will one day oppose them and they try to circumvent it by killing the hero before he can grow up.

A type of VillainBall, and subtrope of LaserGuidedKarma.



[[folder:Anime and Manga]]
* ''Anime/DragonBallZ'':
** Frieza exterminated the Saiyan race in an attempt to prevent any from potentially becoming the legendary Super Saiyan. He missed four (excluding the ones from the movies, which put it at eight or so). Two of them, Raditz and Nappa, worked for Frieza alongside Vegeta, the prince of the Saiyans, but Goku, the fourth, would eventually take Frieza down by becoming the very thing Frieza feared. What's more, after getting turned into a cyborg and coming to Earth to take revenge, both he and his father King Cold are taken down for good by Future Trunks, who turns out to be the son of Vegeta, the other major Saiyan to survive.
** Vegeta even lampshades this shortly before Frieza transforms into his second form.
--->'''Vegeta:''' So, you tried to eliminate the Saiyans, yet you left the strongest one alive! [[SarcasmMode Smooth move!]]
** For bonus points, ''Dragon Ball Minus'' reveals that if Frieza hadn't ordered all the Saiyans back to their home planet to destroy them all at once, Goku wouldn't have even been sent to Earth by his suspicious parents.
** Frieza's cavalier extermination of the Namekians almost became this when he discovered that simply having all seven Dragon Balls wasn't enough to grant his wish. Realising that the Namekians knew something about their use that he didn't, he made a quick but frantic search for any survivors.
* In ''Manga/HunterXHunter'', this seems to be creeping up on the Phantom Troupe, who murdered the entire Kurta clan, maimed their corpses by removing their pretty eyes to sell them, and treat it as [[ButForMeItWasTuesday no big deal]], which further angers the last surviving Kurta, Kurapica. Kurapica has already killed two of their members, and is quite intent on finishing what he started.
** On top of that, if it weren't for some timely intervention from their leader, Kurapica would've killed 6 -- half of the entire group by the time he killed the second. That's how big of an enemy they've made.
* Deliberately invoked in ''Manga/{{Naruto}}'' by [[spoiler:Itachi with the Uchiha Massacre. He leaves Sasuke alive because he ''wants'' to die by his hand.]] It falls through, though; [[spoiler:by this time, Sasuke has abandoned the Leaf Village, and afterward, he decides to actively destroy it.]]
* The Ishvalan Genocide from ''Manga/FullmetalAlchemist'' is an interesting case. The purpose of the extermination was not to prevent a prophecy from being fulfilled or to dispose of a threatening ethnic group ''per se'', but to simply kill as many people as possible (Ishval was chosen simply for its location) - their aim was to kill every Ishvalan, but as you would expect, there were some survivors. Now, one of those survivors was Scar, whose brother was killed in the extermination and who was determined to avenge his death to the State Alchemists... that is, in the beginning. [[spoiler:Later, he does a HeelFaceTurn and starts helping the Elric brothers. In the end, he plays a crucial role in causing the BigBad's EvilPlan to fail and kills Bradley, the man who ordered the genocide - which he would not have done, if the genocide had not existed in the first place.]]
** In [[Anime/FullmetalAlchemist the 2003 anime version]], the purpose was [[spoiler:to make the Ishvalans desperate enough to attempt to create a Philosopher's Stone]] -- something Scar [[spoiler:ends up doing by using an entire army unit of Amestris as the resources for one]]. Meanwhile, [[spoiler:Bradley is killed by one of the soldiers who was a part of the Genocide and was instilled with an immense hatred of the current system by the atrocities committed there -- Roy Mustang.]]
* In ''Anime/YuGiOh'' Millenium World Arc, the Millenium Items were a result of an alchemical ritual that involved sacrificing an entire village through genocide. Unfortunately for the priests of the pharaoh and the civilians 3000 years later, they forgot to kill the young [[spoiler:Bakura]].
** In the [[Manga/YuGiOhGX Yu-Gi-Oh! GX manga]], it turns out to be responsible for that series' BigBad, who was from said village as well, and was understandably pissed-off when it turned out everyone he knew had been horrifically murdered, and tried to kill the pharaoh. It didn't work, and gets him sealed away until he's released some time after the events of the original series.
* ''Manga/{{Bleach}}'': Soul Reapers cleanse [[TheHeartless Hollow]] souls back into the reincarnation cycle while Quincies destroy the soul completely, damaging the Balance of Souls between worlds. To save existence itself, the Soul Reapers wiped out the Quincies but didn't know until too late that most Quincies were in hiding, building their power to retaliate. Only a very few on both sides suspect the two sides are equally to blame.
* In ''Manga/MaoDante'', [[GodIsEvil God wipes out the original human race]] in order to replace them [[PiecesOfGod with himself]], but some of those exposed to his power absorb it and mutate into the first demons.
* In ''Manga/OnePiece'', the World Government was worried that the scholars of Ohara would discover the Void Century, a point in time they didn't want anyone to know about. Therefore, they exterminated the entire island. The lone survivor, Nico Robin, vowed revenge by discovering the Void Century.
* Played with in ''Manga/{{Saiyuki}}'', which inverts the usual perspective of the trope. Hakkai kills off an entire youkai clan in a fit of madness caused by them kidnapping his [[BrotherSisterIncest sister/lover]] Kanan, only to have an apparent survivor of the massacre, Chin Yisou (who is, for bonus points, the child of the clan's head), turn up three years later with clear intents of getting revenge. By that time Hakkai [[ButForMeItWasTuesday fails to recognize him]], complaining bitterly that he thought he murdered them all. Then subverted when Hakkai finally remembers the incident, [[spoiler:realizing that he ''did'' actually kill Chin Yisou back then; the youkai "survived" by turning his own body into a shikigami seconds before death, just so he could get revenge on Hakkai]]. Naturally, Chin Yisou doesn't survive the second time.

[[folder:Comic Books]]
* In one ''ComicBook/{{Lanfeust}}'' spinoff, an alien shapeshifter race is genocided due to their aggressive attacks on many planets. Only one individual survives, but eventually hatches a plot to control the Galaxy and causes much destruction.
* In the comic version of ''ComicBook/{{Wanted}}'', the BigBad Mister Rictus ''deliberately'' invokes this trope, though on a much smaller scale. After murdering an entire family, he leaves a single child alive, banking on the chance that [[CreateYourOwnHero he will grow up to try and take revenge on him]]. Yes, Mister Rictus really is ''that'' bored and crazy.
* The ''ComicBook/ArchieComicsSonicTheHedgehog'' series had this for its Endgame storyline: Dr. Robotnik uses the Ultimate Annihilator to erase Knothole from existence in front of Sonic. A combination of Snively's backstabbing, a mini nuke and Sonic's own two fists ensures that Knothole is restored and Robotnik's done away with permanently.
* An interesting variant in one ''[[ComicBook/TheSandman Sandman]]'' story, it's implied that Despair organises the destruction of Krypton by persuading the AnthropomorphicPersonification of Rao, the Kryptonian sun, to seed life on the unstable planet. However, Despair also intends for there to be [[TheLastOfHisKind a single Kryptonian left alive]], assuming that he will spend his entire life mourning his lost world in despair. That Kryptonian grew up to be [[ComicBook/{{Superman}} Earth's greatest hero, and a symbol of hope to billions of people]], so NiceJobFixingItVillain.
* ''ComicBook/PaperinikNewAdventures'': The Evronians are feared across the galaxy for their destruction and enslavement of many different species. This backfired on them when they destroyed the planet Xerba, where a scientist had performed experiments on herself so she could [[ThePowerOfTheSun acquire the power of a star]]. So to their terror the Evronians were suddenly confronted with a virtually instoppable superbeing gunning after them to avenge her people.

[[folder:Films -- Animated]]
* Occurs in ''WesternAnimation/KungFuPanda2'', overlapping with NiceJobBreakingItHerod; [[BigBad Lord Shen]] is told a prophecy that he will be defeated by a "warrior of black and white", and decides that the correct way to respond to this is to commit panda genocide. Of course, Shen is later defeated by [[TheHero Po]] and his village is avenged. It's played with in a later act when Shen first meets Po, and is a little surprised to find that said panda has no idea what he'd done due to him being a baby when it happened. Further played with at the very end where [[spoiler:the audience learns that the village re-settled elsewhere, so it didn't just backfire -- it straight-up ''failed''. Nonetheless, Shen's actions were what facilitated his defeat, as it would eventually cause the baby Po to end up in the Valley of Peace, which would allow him to get the training he would need to defeat Shen.]]
* In ''WesternAnimation/TitanAE'', the [[EnergyBeings Drej]] destroy earth reducing humanity to a few thousand scattered survivors because they believed us a threat. In the end the Drej are used to power the Titan and create a new homeworld for the human race.

[[folder:Films -- Live-Action]]
* In ''Film/TheChroniclesOfRiddick'', the Lord Marshall of the Necromongers tries to wipe out the Furyan race, due to a prophecy that a Furyan would kill him. He misses (at least) two of them; the titular Riddick is one of them. Funny thing is, Riddick doesn't give a shit about any prophecy and only wants revenge for himself and a few others he might call friends.
* ''Film/TheDarkCrystal'':
** There's a prophecy that a Gelfling will undo the damage to the Dark Crystal, ending the reign of the Skeksis, so of course they go off on a Gelfling killing spree. One of the Skeksis himself, (pretending to be friendly) says "[[SelfFulfillingProphecy Prophecy! Prophecy caused all this trouble!]]"
** In a double invoking of the trope, the male Gelfling Jen is saved by one of the old Mystics and raised among them; on his deathbed, the eldest Mystic sets Jen on his course to defeating the Skeksis. Meanwhile, the female Gelfling Kira is hidden by her mother just before the Garthim take her, and is found and raised by the Podlings. The Skeksis-serving Garthim still raid the Podling villages, to boot.
* In ''Film/TheScorpionKing'', the titular protagonist was one of the few survivors of Memnon's genocide of the Akkadian people. Shortly after the beginning of the film, he ends up being the sole remaining member of his people. Turns out, he is the one who was prophesized to take Memnon down.
* ''Franchise/StarWars'', of course. They didn't kill Anakin and Padmé's children. Nor did they kill Obi-Wan. Or Yoda. They didn't even kill Leia when they killed all the other Alderaanians. This did not work out well for Palpatine.
-->'''Leia:''' The more you tighten your grip, Tarkin, the more star systems will slip through your fingers.
** The ExpandedUniverse shows that the Alderaan Surviviors (those off world when the Death Star came by) almost universally enlisted in the Rebellion after that point. Many other systems began to more openly rebel after the fate of Alderaan came to light. Considering the Emperor wanted to use it to enforce policy on rebellious worlds, the ship was an abysmal failure.
* In ''Film/TronLegacy'', [[spoiler: Clu kills off all the [=ISOs=], [[ArtificialBrilliance emergent]] programs that Kevin sees as a miracle but Clu sees as "imperfect". By the end of the movie, Clu wants to exit the Grid in the worst way, but he gets [[HeroicSacrifice re-merged with Kevin]] while Quorra, the [[LastOfHisKind last ISO, rescued by Kevin]], escapes the grid to the real world with Kevin's son Sam.]] Not quite a genocide backfire since [[spoiler: Quorra didn't land the fatal blow, but Quorra got to leave the Grid while Clu did not.]]
* ''Film/TheGodfatherPartII'' The local ganglord kills Vito Andolini's father, then his brother when the brother tries to get revenge, then his mother when she tries to protect Vito ('because he's slow'). Vito then has to leave Sicily for America, where he becomes Vito Corleone. He then returns to Sicily to off the ganglord.
* Skynet in the ''Franchise/{{Terminator}}'' series wipes out most of humanity, but the survivors eventually destroy it.
* Parodied in ''Film/KungPowEnterTheFist'' when Master Pain kills TheChosenOne's entire family before attempting to kill him. However, even as an infant The Chosen One is too strong to take on in a straight fight so Master Pain just burns the house down. The Chosen One, of course, survives and grows into adulthood and eventually defeats Master Pa-, Betty.

* Ublaz Mad Eyes of the ''Literature/{{Redwall}}'' series sent a group of corsair minions to destroy Holt Lutra (a community of otters) in order to procure a special set of pearls that he wanted for his crown. Unfortunately for him (and a lot of other people), Grath Longfletch, the leader of the group's daughter, just barely survived, and when she recuperated, dedicated her life to killing every corsair she could find. She is ultimately a key member of the group from Redwall that travels to his island and defeats him. Although she doesn't actually know who ''he'' is, and is not personally responsible for his death -- [[spoiler: Martin has that honor.]]
* In ''Literature/TheGraveyardBook'' this is the reason why [[spoiler:the Jacks of All Trades killed Bod's family]].
* Arguably happens in ''Literature/{{Dune}}'', where [[spoiler:the Baron Harkonnen kills his rival, Duke Atreides, and attempts to do the same with his only son, thus wiping out the Atreides family line and ending the millennia old Atreides/Harkonnen blood feud. At first he thinks he's successful, but they [[NeverFoundTheBody never find the boy's body...]]]]
* In R.A. Salvatore's Literature/ForgottenRealms novel ''[[Literature/TheDarkElfTrilogy Homeland]]'', one Dark Elf house in Menzoberranzan is punished for failing to kill off ''all'' of a rival house's noble family by the DeadlyDecadentCourt, which sentences the attacking house to be exterminated ''properly''. This is built into their "law"; total extermination is fine, just don't leave any witnesses. Of course, only surviving nobles count as witnesses, not ordinary underlings. Wouldn't want to actually ''discourage'' [[KlingonPromotion competition]], now. And it would be a waste of people to kill everyone.
** Ironically, even this fails. One of the recruitable characters in the VideoGame/BaldursGate series is one of the few surviving members of this family.
*** Then again, she ''is'' a non-Lloth priest, so she may have left Menzoberranzan before.
* In the novel ''[[Literature/TheRiftwarCycle Talon of the Silver Hawk]]'', the eponymous character is almost the LastOfHisKind, and ends up working (under the name Talwin Hawkins) for the guy who ordered it in a long-term plot to bring him down.
* Played with in Creator/JackVance's ''Literature/TheDemonPrinces''. The hero wouldn't have had any reason to devote his life to tracking down and killing the titular villains if they had chosen a different space colony to raid on that day.
** Also different in that it was the other survivor, his grandfather, who groomed him to be an instrument of justice. The hero may have just gone off to life peacefully somewhere else if given the chance early on.
* In the first book of Laurie J. Marks' ''Literature/ElementalLogic'' series, a whole tribe is killed off because of a prophecy that indicates Bad Things for the invading army if a single member of the tribe survives. Of course, one (and only one) tribe member escapes...
* In C.S. Friedman's ''Literature/ColdfireTrilogy'', the immortal and extremely narcissistic MagnificentBastard character of the series left one of his children alive when he slaughtered his family to make a pact with a demon. His descendants were free to live without being troubled, provided they ''never'' laid claim to his title as the Neocount of Merentha. If any of the male descendants did so, then The Hunter would again lay waste to his entire family, save one. He was vain enough that he always left the one descendant who looked the most like him alive. Of course, [[spoiler:this bit him in the ass when the survivor of the last generation played a key role in the Patriarch's scheme to destroy him.]]
* In Jacqueline Carey's ''Literature/TheSundering'', the AntiVillain Satoris wipes out a desert tribe that sent a child to destroy him. Unusual in that the child had already been dispatched by that point; however, he had nothing in particular against Satoris until his village was destroyed, and it's strongly implied that he could have been talked out of his quest if that atrocity hadn't been committed.
* It's implied that Garoth Ursuul of ''Literature/TheNightAngelTrilogy'' commits genocide often enough that he actually has a ''list of rules'', among them is "You will always miss one." This is never shown to actually come back to haunt any Ursuuls in the book, however.
* Happens lots of times in Creator/DavidWeber's ''Literature/EmpireFromTheAshes'', as the [[OmnicidalManiac omnicidal]] Achuultani, themselves a last remnant from a campaign of genocide by a hostile power in their own galaxy, have ''nearly'' wiped out humanity several times. We now have [[ThatsNoMoon planetoid dreadnoughts]] whose ''[[MisappliedPhlebotinum star drives]]'' can [[RememberWhenYouBlewUpASun cause supernovae]] when used too close to a star, and each has combat capability equivalent to [[ZergRush hundreds of thousands]] of Achuultani ships. Oh yes, and [[ShameIfSomethingHappened we know where they live]].
** On the positive side of things for the Achuultani, due to certain plot developments and revelations, it is quite likely the eventual human counter-attack will include willing ''Achuultani'' participants seeking to free their fellows [[spoiler: from the [[AIIsACrapshoot AI]] that has effectively enslaved them via the cycle of near-genocides and a liberal definition of crisis]].
* Implied at the end of ''Literature/OutOfTheDark'', again by David Weber. The Shongairi announced themselves to Earth with a series of [[ColonyDrop Colony Drops]] on Earth capitals, and when controlling Earth proved to be impossible tried to exterminate mankind with a biological weapon. They failed, and at the end Humans knows how to replicate Shongairi technology and where they live.
* A small-scale version of this is the core plot of Creator/MercedesLackey's first [[Literature/HeraldsOfValdemar Vows & Honor]] short story ''Sword-Sworn''. A large force of bandits, with the aid of a wizard to strike down the sentries, ambushed the Shin'a'in clan Tale'sedrin on the way back from a horse fair and killed every one of them... save the skinny teenager they did [[NotQuiteDead not bother making sure of]] after strangling and gang-raping her.
* ''Literature/LastLegionary'': The BigBad deciding the Legions of Moros were the major obstacle to him conquering the galaxy and that eliminating was the best course of action? Doesn't work out so well. The Legions weren't even aware of the Warlord's existence prior to the attack that left Keill the only survivor of his race.
* ''Literature/TheBelgariad'': the line of Riva was supposedly killed off by Queen Salmissra. One prince survived, and his descendants were hidden by Polgara and Belgarath.
* ''Literature/LordOfTheRings'': Sauron believed that he had killed off the line of Isildur. He forgot about Aragorn.

[[folder:Live-Action TV]]
* A very longterm example occurs in the ''Series/BabylonFive'' universe. The Hyach once shared their planet with another sentient species, the Hyach-do. The two races coexisted peacefully for thousands of years, and even intermarried, until the Hyach exterminated the Hyach-do in a frenzy of religious fervor. Centuries later, it was discovered that the declining birth rate of the Hyach is because interbreeding with the Hyach-do was necessary to sustain the Hyach genome. Thus, in wiping out the Hyach-do, the Hyach have doomed themselves to extinction as well.
* Played with in ''Series/ChikyuuSentaiFiveman'' where the BigBad was defeated by the flower of the first planet he wiped out (he forgot the memo to destroy it completely).
* ''Series/DoctorWho''
** A rare heroic example: The Doctor has attempted genocide on the Daleks at least four times. [[JokerImmunity It never takes.]] They just hate him even more now than they did before.
** He did deliberately avoid committing genocide in ''Genesis of the Daleks'', giving as his reason that while the Daleks are indeed evil, omnicidal Space Nazis, a lot of good has come out of people banding together to fight them. That decision sure came back to bite him in the ass.
** After the Doctor supposedly wiped out the Daleks and Time Lords when the Time Lords were prepared to destroy time itself, one more Time Lord managed to escape the War some time before. [[spoiler: Not only is he his (other) arch-enemy, but the rest of the Time Lords use him to escape]].
** The Doctor ended the Time War through the use of some unspecified superweapon, which was supposed to kill all the Daleks and accidentally killed all the Time Lords, but Daleks keep popping up. It becomes clear in the Tenth Doctor's last episode, however, that this is because [[spoiler:''he wasn't just aiming at the Daleks'']].
*** In the 50th anniversary special, it's revealed that rather than destroy the Daleks and the Time Lords [[spoiler:the superweapon in question convinced the Doctor, with help from two of his next incarnations, to hide Gallifrey in a pocket dimension.]] Ultimately, it [[spoiler:would have been the Daleks aiming at themselves.]]
* ''Series/GameOfThrones'':
** House Bolton tried to wipe out the Stark bloodline. The Stark remnants fighting back and Ramsay's own StupidEvil tendencies led to the Bolton bloodline's extinction instead.
** [[spoiler:Arya]] takes a particular delight in pointing this out as [[spoiler:all the males of House Frey die from poisoned wine, annihilating it as a house]], saying they should have wiped out ''all'' of the Starks, root and stem, but since they didn't, they are [[KillEmAll where they are now]].
-->''Leave one wolf alive, and the sheep are never safe''
* Tried by Darken Rahl in ''Series/LegendOfTheSeeker''. He got wind of a prophecy that the True Seeker would be born in a certain town, so he had his troops, led by his most trusted lieutenant, to kill all the first born sons in the town. Sure enough, Richard was spirited away, and when Rahl finds out 20 years later, [[YouHaveFailedMe he executes the lieutenant]].
* In ''Series/{{Lexx}}'' His Divine Shadow was very thorough in wiping out the Brunnen-G in order to thwart a prediction that the last of their race would destroy him, but he made the mistake of [[TemptingFate mocking the prophecy]] by turning the last Brunnen-G Kai's corpse into an [[IdiotBall undead immortal killing machine]] under his control. [[spoiler:The Divine Shadow himself is the parasitic essence of the last Insect that the Brunnen-G missed when they defeated the Insect Civilization.]]
* ''Franchise/StargateVerse'':
** In ''Series/StargateSG1'' where Daniel lands in an alternate grimmer dimension where the Goa'uld have invaded Earth, an cold-hearted O'Neill sends a nuke to the Jaffa homeworld upon learning the location from Daniel who wanted. This bites him in the ass when he pleas Teal'c to think of his son, who had been killed by the nuclear strike.
** In ''Film/StargateContinuum'', Baal is smart enough to know that trying to exterminate the Tau'ri will only cause eternal resentment among the survivors who will try and take revenge. Instead, he tries to woo humanity to his side peacefully with the intention of turning them into the next generation of Jaffa. Unfortunately for him, his wife didn't quite see it that way, and decided to do a bombardment of the planet after murdering him.
* Near the series finale of ''Series/StarTrekDeepSpaceNine'', the Cardassians have at that point lost all standing with the Dominion and are not much more than unwilling vassals. This leads elements of the [[LaResistance the civilian population]] to subvert the Dominion war effort through acts of sabotage. As a result of one particular incident which nearly cost them a battle, the Female Changeling orders a major Cardassian city to be wiped out by orbital bombardment as an example, and announces that the Dominion will destroy one city for every act of sabotage committed. After hearing this, however, the entire Cardassian fleet does an abrupt HeelFaceTurn in favor of TheFederation instead, as well as getting many Cardassian soldiers on-planet to defect. This in turn prompts the Dominion to to start slaughtering the Cardassians en masse, but since her subordinate proceeds to send out most of their troops stationed at the base to do so, this leaves their installation critically under-guarded when Damar and his crew attack Dominion Headquarters. About half of the force that storms it had been ''guarding'' it up to that point.
** Irony time: the Cardassians used the [[HistoryRepeats same tactics during their earlier Occupation of Bajor]], with the same results (except they were smart enough to not have Bajorans fighting alongside them on the front lines of an interstellar war at the same time).
* ''Series/StarTrekVoyager'' had a variant: The Krenim were going around exterminating entire races from the timestream to make it as though their empire never fell. Unfortunately, this was a hit or miss endeavour. Sometimes, it resulted in their empire at near full strength, others it set them back centuries. But the first ''real'' backfire that happened was that one of the races that helped destroy their empire in the first place also introduced some disease treatment whose absence caused the death of the project lead's wife, and none of the altered timestreams had a cure. Since then, the project lead was desperately searching for a way to fix things for his own ambitions. [[spoiler:Ultimately, the problem is solved when Voyager [[RammingAlwaysWorks rams]] the superweapon when it's about to fire, causing it to RetGone ''itself''.]]
* Uther Pendragon in {{Series/Merlin}} attempted to kill all the magic users and dragons he could find. Now that he's cleared out all the harmless, innocent ones, the more violent and powerful ones are gunning for his blood. He did manage to kill all the dragons, but decided to keep the last one as an example. When it gets loose, it very nearly burns his city to the ground. And just when you think he's too much of a KarmaHoudini [[spoiler: his daughter Morgana turns out to be magical and kills him.]]
* In ''Series/BarbariansRising'', [[FromNobodyToNightmare Viriathus is a mere shepherd]] who escapes a Roman punitive slaughter of Lusitanian tribesmen and morphs into a reluctant RebelLeader.

[[folder:Mythology and Folklore]]
* Myth/KingArthur learned that he would be destroyed by a child born in a certain month, he had all the babies from that month gathered together, put on a ship and sent to die. The ship crashes and kills every one of them... except for one: Mordred. This is one of the newer versions of the much-revised legend, however. Earlier versions of the story have Mordred as his nephew, there is no such genocide, and Lancelot is nonexistent.
** In one more recent version, a cunning Myth/KingArthur knows how a GenocideBackfire works and instead conscripts all the boys of that age group and makes them squires. All of them but one love him. The one? [[YouCantFightFate Mordred]].
** The Webcomic/ArthurKingOfTimeAndSpace version was also smart enough to know that YouCantFightFate and Merlin even cites the above example of sending them on a ship as just an pointless atrocity. However, the well-meaning but dim Sir Balin only overheard part of the conversation and ordered the ship plan without either of their knowledge, setting up Arthur's inevitable downfall.
* Literature/TheKalevala has this: Untamo kills his brother Kalervo and his clan over petty neighborhood squabbles, leaving only a pregnant woman alive. The woman in time gives birth to Kullervo, who later kills Untamo - and wipes out his clan, for good measure.

[[folder:New Media]]
* In the reddit series Chrysalis, the Xunvir Republic completely wipes out all life on Earth [[spoiler: because it was more profitable than enslaving humanity]]. Every Human is killed, but they left behind a single sentient Von Neumann machine to return the favor.

* Literature/TheBible provides some examples:
** In the Literature/BookOfExodus, Pharaoh commanded that all male Hebrew babies must be put to death. The lone escapee, Moses, became the freer of the Hebrews. Worst of all, the Egyptians got the infanticide reversed on them when the tenth plague struck down all their firstborn.
** [[UsefulNotes/{{Jesus}} Jesus Christ]]. Herod could not kill all the Jewish boys who had been born under the star of Bethlehem because Jesus was in Egypt. And John the Baptist was in hiding in the wilderness with his mother. However, neither Jesus nor John ever actually did anything to Herod; he just died of old age a couple of years later, while they were still small children. (Specifically, he died of chronic kidney disease and [[http://en.wikipedia.org/wiki/Fournier_gangrene Fournier gangrene]], the latter of which is often interpreted as [[{{God}} Jesus' dad]] invoking this trope.) Though his grandson, [[DeadGuyJunior Herod]], got killed by an angel for persecuting the early church a couple of decades later.
** In the Literature/BookOfEsther, we have [[EvilChancellor Haman]], who ends up HoistByHisOwnPetard on the gallows/spikes (your translation's mileage may vary) he had built to kill Mordecai.
** Literature/BooksOfKings: Queen Grandmother Athaliah of Judah attempted to extirpate the whole David family line. One boy, Joash, survived...

[[folder:Tabletop Games]]
* In the ''TabletopGame/BattleTech'' universe, during the Clan invasion, Clan Smoke Jaguar [=WarShips=] [[OrbitalBombardment powered up their weapons and glassed]] a Draconis Combine city in an attempt to break the back of the stubborn Combine resistance. Not only did this serve to alienate their allies, drive the Combine to even greater heights of stubborn defense, but, when a defector revealed the Exodus road, the closely guarded secret route to the Clan homeworlds, the battle cry (and mission) of the armada of the Restored Star League Defense Force was "Clan Smoke Jaguar Must Die!"
** Similarly, the Kentares Massacre during the First Succession War had this effect. The deliberate murdering of 90% of Kentares IV's population in revenge for the assassination of the Draconis Combine's Coordinator not only put new resolve into a near-defeated Federated Suns (leading to the Suns' RoaringRampageOfRevenge that took back all the territory lost to them), but also caused mutinies, desertions and suicides among the Draconis Combine's military and also lost the DCMS the services of one of the most elite mercenary units of the time.
* In Rokugan, the setting of ''TabletopGame/LegendOfTheFiveRings'', the Scorpion Clan serve as the Emperor's Underhand. They protect the Empire from hidden or subversive threats, the sort that can't be met with force of arms. Rokugan's CIA, basically. Sounds good, right? Well, the leader of the Scorpion Clan, Bayushi Shoju, discovers some hidden prophecies that foretell the return of [[SealedEvilInACan the dark god Fu Leng]] ... at the hands of the last of the imperial Hantei line. So, Shoju does what any well-meaning defender of his homeland would do. He unseals the [[ArtifactOfDoom Bloodsword "Ambition"]] and uses it to kill the Emperor and his family, while his army seizes the Imperial City in what would later be known as the Scorpion Clan Coup. Of course, the Emperor's weak, borderline-retarded son manages to survive, and when the Coup is inevitably foiled he is installed on the throne with Shoju's widow as his wife, where she proceeds to poison and corrupt him for years until he's so weak that [[DemonicPossession bad things start to happen]].
** Of course, with the rise of [[spoiler:Daigotsu]], he might have had the prophecy completely wrong anyway.
* ''TabletopGame/MagicTheGathering'' features Garruk, who was forced to join the army as a child. His father hid him instead, and he came back and killed the lord.
** The destruction of Chandra Nalaar's village on Kaladesh by Consulate enforcer Baral, leading to Chandra's spark igniting, had two survivors: Chandra, who planeswalked away, and Chandra's mother, Pia. Pia dealt with it by leading a rebellion against the Consulate, and when Chandra returned, she dealt with it by joining in, with Baral finishing the story [[CruelMercy locked away forever with nothing but his scars and the knowledge that the world is moving on without him]].
* ''TabletopGame/{{Warhammer 40000}}'':
** Inverted ''here'' of all places. When the Imperium first encountered the Tau, they were a race of non-technological primitives living on one world. They were scheduled for routine genocide ([[CrapsackWorld it's that kind of universe]]), but the paperwork got lost somewhere and a Warp storm cut off the Tau system from the rest of the galaxy. A thousand years or so later, and the Tau are the fastest-growing alien empire on the Eastern Fringe, and a major thorn in the Imperium's side. Keep in mind the Tau never realized the Imperium even existed, much less had them slated for death (and the Tau are kept carefully ignorant how just how much bigger the Imperium is compared to them).
** The orks have a built-in version where their corpses release spores that eventually grow into orks, and the knowledge of how to make guns, vehicles and starships is hard-coded into their DNA. The only thing to slow them down somewhat is burning the corpses, but even that isn't enough.

* ''Theatre/TheTrojanWarWillNotTakePlace'': Hector claims that the nation he fought was the most barbaric one, so there will no longer be wars because the Trojans killed every child. Except one. Andromache answers that this child will have uncountable descendants, so in some centuries the world will be at total war.

[[folder:Video Games]]
* In ''[[VisualNovel/AceAttorneyInvestigationsMilesEdgeworth Ace Attorney Investigations 2]]'', a FakeKing, a DirtyCop, and an AmoralAttorney once teamed up to form an international conspiracy that would LeaveNoWitnesses. Unfortunately, one little boy managed to escape, and after they spent over a decade trying to hunt him down, he finally snapped, TookALevelInBadass, and decided to strike back at them, ultimately growing up to become [[spoiler:the game's BigBad and FinalBoss.]]
* In ''VideoGame/{{Bastion}}'', the Caelondian government [[spoiler:had the Calamity created in order to completely eradicate the Ura to prevent them from ever having to go to war again. When he finds out, the Ura scientist that created the Calamity sabotages it so that it destroys the world instead.]]
* In ''VideoGame/FinalFantasyIV'', the king of Baron ([[spoiler:Actually Cagnazzo, archfiend of Water, [[FakeKing in disguise]]]]) tries to wipe out the Summoners. He does a pretty good job, but he misses one, the young summoner Rydia. However, it isn't played completely straight in that the backfire mainly came from the main character defecting to eventually take him down rather than Rydia herself. The main character also teams up with Rydia to defeat Cagnazzo's master, who the Summoner genocide was supposed to benefit.
** In ''VideoGame/FinalFantasyIX'', the summoners of Madain Sari are also wiped out by the BigBad long before the game... except for Eiko and [[spoiler:Garnet, whose mother whisked her away to Alexandria]].
** In ''VideoGame/FinalFantasyVI'', Kefka poisons the populace of Doma, and one of the only survivors ends up being a player character who potentially takes him down. Kefka differs from most examples of this trope as he did it basically for [[ForTheEvulz the hell of it]] rather than some overarching goal of self-preservation.
* Videogame/StarWarsTheOldRepublic, introduces a heroic version as part of the backstory; A large part of the Sith Empire's motivation is revenge after the Republic [[WouldBeRudeToSayGenocide exterminated]] the rest of their society.
** And in Videogame/KnightsOfTheOldRepublic, Bastila, one of the few people who escaped the bombardment of Taris, is the exact person Malak intended to kill when launching the planet wide attack.
** The [[PlayerCharacter Jedi Exile]] in ''VideoGame/KnightsOfTheOldRepublicIITheSithLords'' has mostly survived the ongoing Jedi Purge by being a) cut off from the Force and b) wandering the Unknown Regions; upon returning to the Republic and finding that the Sith have killed most of the Jedi and are coming after you, the Exile - motivated by [[KarmaMeter either justice or self-preservation]] - proceeds to grind the Sith Triumvirate into dog meat and destroy both their remaining strongholds, the ''Ravager'' and the planet Malachor V.
* The PlayerCharacter in ''VideoGame/JadeEmpire'' is the last surviving Spirit Monk, an order who were slaughtered so that the Emperor could steal the power of their goddess, the Water Dragon, to defy the Heavens and end a severe drought. [[spoiler:The player character survives because of Master Li's plan and Master Li manipulates him into killing the Emperor for him so that Li can steal both the throne and the Water Dragon's power. In one ending, it works.]]
* In ''VideoGame/GuildWars: Prophecies'', the White Mantle ritually identifies the Chosen and then [[HumanSacrifice sacrifices them to their gods]]; discovering this is what drives the PlayerCharacter to turn on the Mantle. Then the PlayerCharacter is revealed to also be Chosen...
* The Lombaxes and Cragamites in ''VideoGame/RatchetAndClank Future: Tools of Destruction''. The Lombaxes sealed the AlwaysChaoticEvil Cragamites in AnotherDimension, save for one Cragamite child they took pity on. This lone Cragamite, Emperor Percival Tachyon, then raised an army and wiped out the Lombaxes [[DontYouDarePityMe for daring to pity him]]. But he missed Ratchet, who proceeds to trap him in AnotherDimension with the rest of his mad race.
* Played with in the ''Franchise/{{Metroid}}'' series. ''Metroid 2: Return of Samus'' has Samus tasked with exterminating the Metroids on their home planet of [=SR388=]; the game ends with Samus sparing a single hatchling, which has imprinted on her. ''Super Metroid'' starts off with scientists studying the larval Metroid making the discovery that the Metroids have abilities that could be used for the good of galactic civilization, right before the Space Pirates massacre the researchers and abduct the larva so they can build another Metroid army; the next time Samus encounters the larva, it's grown to horrendous proportions and almost kills Samus before it recognizes her. Then, during the final battle, it performs a [[TearJerker truly heartbreaking]] HeroicSacrifice, saving Samus from Mother Brain's onslaught and giving her the unstoppable Hyper Beam weapon. (Then ''Metroid Fusion'' reveals that the Metroids on [=SR388=] were keeping an even more dangerous threat in check, which is [[NiceJobBreakingItHero another trope entirely...]])
** Samus herself is portrayed as the sole survivor of a Space Pirate attack on the mining colony of K-2L. Who would have thought that cute 3-year-old girl would come back to bite them in the ass so hard?
* [[NamesToRunAwayFromReallyFast Iosa the Invincible]] of ''VideoGame/{{Iji}}'' had her homeworld [[EarthShatteringKaboom Alpha Struck]] by the Tasen. She didn't take that very well.
** For that matter, Iji is one of two known human survivors of the Tasen Alpha Strike and subsequent invasion of Earth, and the other is playing MissionControl for her.
* ''Franchise/{{Halo}}'':
** The Covenant's attempted genocide on mankind ends up being its downfall. It started in 2525 when the High Prophets found out that the humans were the inheritors to the Forerunners, the species that the Covenant worshiped as gods, and they realized that the truth about it would splinter the Covenant if it ever was spread. They decided to wipe out humanity so that no one would find the truth. 30 years later, the war sets off a chain of events which leads to all the High Prophets being killed, many former Covenant Elites allying with humanity, the Covenant capital ''High Charity'' falling to the Flood only to be destroyed by Master Chief, and the Covenant itself now nothing but a myriad of opposing factions.
** The more direct trigger for the Covenant's fall was when the Prophets ordered their forces to genocide the Elites because the former felt the latter were no longer reliably loyal; instead, the Elites team up with humanity and destroy the Covenant.
** As first revealed in ''Literature/TheForerunnerSaga'', the Forerunners and the ancient human interstellar empire fought a devastating war, with the Forerunners winning and literally blasting humanity back to the Stone Age. Unfortunately for them, the humans had plenty of research and experience on the Flood, which was destroyed when Earth fell. Then the Forerunners themselves get wiped out by the Flood.
** The ''Halo''verse has an even more ancient example, to which this trope applies regardless of [[UnreliableNarrator which side is telling the story]]. [[spoiler:The Forerunners themselves had RecursivePrecursors, called...the Precursors, who created both humanity and the Forerunners. What happens next is rather unclear. According to the Forerunners, the Precursors decided the Forerunners were a mistake and tried to wipe them out; however, the Forerunners struck first, and all but wiped out the Precursors. According to the Precursors, they simply decided that the Forerunners shouldn't have the Mantle, with the Forerunners' attack being completely unprovoked. Either way, the few surviving Precursors broke down into a dust which, 10 million years later, ''would become the Flood!'']]
* The third variant occurs in the ''VideoGame/AgeOfEmpiresIII: The Warchiefs''. Chayton Black has some moral reservations about killing women and children just to help the gold rush along, so he defects to the Sioux he was ordered to kill. This ends badly for Billy Holme.
* A fairly straightforward case in ''VideoGame/{{Bayonetta}}'': the BigBad [[spoiler:Father Balder]], the last Lumen Sage, began the Witch Hunts against the Umbra Witches (in which the titular heroine is a member of) more or less ForTheEvulz. Naturally, Bayonetta stops this plot.
** [[spoiler: [[VideoGame/{{Bayonetta2}} And then it turns out that the truth is more complicated than that]].]]
* In ''VideoGame/PrinceOfPersiaTheForgottenSands'' for the PSP ([[ReformulatedGame there are four different games on different consoles under that title]]), an ifrit hears of a prophecy stating that a lonely hero with royal blood will kill him, so he starts assassinating people who are part of Persia's royal family. The Prince of Persia, upset over the deaths of his cousins, then tracks down and kills the ifrit. SelfFulfillingProphecy.
* In VideoGame/MetalGearSolid2, the Patriots deliberately invoked this when they had Dead Cell liquidated (IE, most of its members killed off) for terrorist attacks it apparently committed. In actuality, the Dead Cell unit was actually framed for the terrorist activities by the Patriots (in other words, it was actually the Patriots who committed terrorist attacks on their own country), and more importantly, they deliberately allowed some survivors to exist in Dead Cell specifically to get them angered enough to attempt to challenge them and more importantly further use them in the S3 plan.
* In ''VideoGame/DragonQuestII'', Hargon kills everyone in Moonbrook, but [[BalefulPolymorph turns the princess into a dog]] rather than kill her.
** In ''VideoGame/DragonQuestIV'', the Hero's village is destroyed by the BigBad's minions, but he's hidden away at the time. Naturally, the Hero was the ''only'' person in the village that the BigBad actually gave a damn about. At the time, the BigBad thought the attack was a complete success, as one of the other villagers [[VoluntaryShapeshifting transformed into a copy of the Hero]] and [[HeroicSacrifice died in his place]].
* In ''VideoGame/SupremeCommander'' a paranoid Earth Empire commander waged war with the [[HigherTechSpecies Seraphim]] and their human followers, but they were easily defeated by their numbers and weapons, in their last ditch effort take them out they unleashed a bio weapon that only targets the Seraphim slowly killing them all. But what they killed was only a very small portion of the Seraphim race who live on the other side of the quantum realm, in ''Forged Alliance'' they cross into human realm and conduct their own genocide on the humans.
* A variant occurs in ''VideoGame/GodOfWar II''. While Kratos is off on his quest to find the Sisters of Fate, Zeus decides to wipe out his beloved Sparta. One soldier (whom you met in the beginning of the game) survives the attempt and tries to seek out the Sisters himself. [[spoiler: You end up fighting and killing the poor guy, but not before he tells you what happened to Sparta.]] This only serves to make Kratos ''[[UpToEleven even more pissed]]'' and [[RoaringRampageOfRevenge hellbent on taking revenge on Zeus.]]
* In the first ''VideoGame/{{Homeworld}}'' game, this is how the Taiidan Empire meets its end. After the Kushan perfect hyperspace technology, [[spoiler:the Emperor decides to invoke a four-thousand-year-old treaty that the race had forgotten, which was that they were not permitted to develop any hyperspace technology. This results in the near-genocide of said race, and in addition to causing the survivors to get royally pissed off and begin a war against them, also results in a massive rebellion rising up due to public outrage of an essentially unprovoked attack on a fledgling race that had just started interstellar travel]]. By the end of the game, the Kushan fleet and Taiidani rebels assault the Taiidani homeworld in joint force, destroy the defense fleet as well as the Emperor's flagship, then make landfall and shut down the cloning facilities that housed replacements, shattering the Empire entirely except for a few remnants with little power.
** The backstory reveals that this is how the original Hiigaran Empire fell. They were on fairly even terms with the rival Taiidani, until the Hiigarans got their hands on one of the Great Hyperspace Cores, allowing them to jump whole fleets enormous distances with pinpoint accuracy. They use it to jump their fleet into orbit of the original Taiidani homeworld and lay waste to it before jumping back. Outraged, the Bentusi and the other races demand that the Hiigarans surrender the Core, as they clearly abused its power. Instead of peacefully handing over the Core, the Hiigaran fleet attacked the Bentusi, who promptly wiped out the whole fleet. As a result, the Hiigarans were then defenseless against the pissed-off Taiidani in need of a new homeworld. Cue the CurbStompBattle and the exile (and nearly retributory genocide) of the Hiigarans.
* In ''VideoGame/DragonAgeOrigins'', during the Human Noble origin, Arl Howe attempts to wipe out the entire Cousland line when the main army leaves Castle Highever to fight the darkspawn. However, thanks to the Grey Warden Duncan, the player survives, becomes a Warden, gains armies of support and powerful allies, and eventually returns to Howe's manor to express your disapproval of his ambitions by rearranging his face.
** In other origins, the latter still happens but for a different reason. It's briefly mentioned that the only member of the Cousland family to survive was the Human Nobles older brother, who has no involvement in getting back at Howe.
* DoubleSubverted in ''VideoGame/MegaManZX'' and its sequel, ''VideoGame/MegaManZX Advent''. In a similar manner to the [[VideoGame/MetalGearSolid2SonsOfLiberty S3 Plan]], Serpent (and ultimately Albert) were heavily implied to have deliberately spared only a handful of people during Maverick Raids in order to get them to become Mega Men and thus participate in the Game of Destiny to become the Mega Man King. However, by the end of the game, regardless of the deliberate attempt to spare them or not, it still put an end to their plans and presumably the Game of Destiny.
* Genocide attempts has happened quite often in the history of the VideoGame/WorldOfWarcraft, though only a few have backfired.
** One that did backfired was the attempted genocide that the [[AbusivePrecursors Mo]][[DespotismJustifiestheMeans gu]] tried on their {{Servant Race}} the Saurok. To elaborate, after their conquest of [[CrapsaccharineWorld Pandaria]], the Mogu created the Saurok to police the enslaved races. Soon enough the Saurok realized that the Mogu had no way to control them, since they were given free will and fighting prowess in both sword and sorcery, so a few of their legions rebelled against their Mogu officers. This caused the Mogu emperor to decree the ethnic cleansing of the Saurok race. However 2 Saurok legions were stationed in the [[BeePeople Man]][[ProudWarriorRaceguy tid]] lands at the time, and managed to hide there despite the Mogu sending many armies of slaves after them, arguably since [[EnemyMine the Mantid were not too happy of having the Mogu invading their territory]]. Even [[FromBadToWorse worse]], when [[spoiler:the succesor of the Mogu emperor moved his palace to the Krassarang Wilds to oversee the genocide of the Saurok, the surviving legions took him by surprise and threw him off a cliff.]] ''Never succeeded'' indeed.
* ''VideoGame/SineMora'': Enkies are the mass-victims of FantasticRacism. Enkies are also vital to psychic time travel. The empire (unadmittedly) runs on time travel. DO THE MATH.
* In the backstory of ''VisualNovel/HatofulBoyfriend'' a version of the bird flu becomes so virulent that in two years ''seventy percent'' of humanity dies and there's no sign of stopping. In desperation humans created a virus of their own, an "avian annihilation" virus that would kill all birds. It kills many, but in the resistant ones there is [[GoneHorriblyWrong another effect]] and the birds become [[UpliftedAnimal uplifted]], and immediately go to war on humanity. Thirty years later less than five percent of the human population remains and signs a treaty of surrender, and the world belongs to birds.
* In ''[[Videogame/{{X}} X3: Albion Prelude]]'', the Argon start a interstellar war after they suicide bomb the jewel of the [[PlanetTerra Earth State]], the Torus Aeternal, an orbital shipyard and city [[RingworldPlanet ringing the Earth's equator]], killing millions from the initial explosion and [[ColonyDrop subsequent deorbiting debris]]. In response, the Earth State [[RoaringRampageOfRevenge immediately goes on a rampage]]. In-game, the Terran fleets will handily curb-stomp the Argon courtesy of their [[HumanityIsAdvanced technological might]] and superior capital ships, though plot-wise the Argon use reverse-engineered Von Neumann ships to push the Terran fleet to the brink of destruction. Of course, the Argon never got to finish the job because at that point the PortalNetwork was shut down by the {{precursors}} to stop the genocide, meaning the Argon were suddenly without reinforcements or even a government.
* In ''VideoGame/{{Fallout 4}}'', if the player sides with the Railroad, the Brotherhood of Steel's stated goal to eradicate the [[ArtificialHuman Synths]] gets ''them'' eradicated.
* In the ''Franchise/MassEffect'' backstory the quarian government launched an attempted genocide of the newly-sentient geth machine race in fear of the geth [[TurnedAgainstTheirMasters turning on them]]. The geth [[RobotWar fought back]], [[http://masseffect.wikia.com/wiki/Geth_War#The_War committed their own genocide]] that eradicated 99.9% of the quarian population, and the few surviving quarians ended up driven from their homeworld. To add insult to injury they only survived at all because the geth, being unable to fully comprehend the ramifications of wiping out the last 0.1%, let them go.
** This trope shows up again ''VideoGame/MassEffect3'', potentially taken either way. The geth (except for a RenegadeSplinterFaction that works as mooks for a third party, who tried to commit genocide on ''all'' other life due to their worship of the Reapers) after the war proceeded to occupy the former quarian worlds for centuries and kill anyone who came near, not overtly bothering the outside world but essentially dooming the few remnants of the quarian species to slow [[DyingRace extinction]] due to their biological dependence on said worlds,[[note]]Mass Effect: Ascension mentions that the quarian species would be likely to survive another century without a free and empty planet to settle on, which they haven't been able to find outside of the geth systems[[/note]] which the geth openly admit they don't need. It gets a bit more complicated as [[HiveMind Legion,]] a geth who can be recruited as a team mate, will also mention the geth are open to peace [[IdiotBall yet the quarians attack them 100% of the time if they believe they have an advantage.]] and the conflicting midset in response to their ancestors near genocide causes a large rift in the Conclave. Then in ''VideoGame/MassEffect3'' present-day quarians, having developed a new anti-geth weapon, attack and try to wipe them out in an attempt to regain their lost territory. Depending on the player's choices, either the few surviving quarians can eradicate the machines their ancestors created, the geth can wipe out the last descendants of their creators as they are in the process of trying to eradicate them, or [[TakeAThirdOption clever manipulation of demographics and politics]] on the player's part can end up in both sides agreeing to a peace.[[note]]Specifically, Shepard wipes out the small portions of the geth population opposed to peace (the remnants of the aforementioned splinter faction), rescues and earns the loyalty of the influential geth platform Legion, and helps install/save two pro-peace quarians as two of the five leaders of their species.[[/note]]
** In the main storyline itself, although the Reapers make a very effective attempt to erase all traces of themselves and information necessary to beat them before heading out to await the next cycle, it doesn't always work. In the previous cycle [[spoiler: they were unaware of Ilos and the last Protheans sabotaged the Citadel's Keepers, preventing Harbinger from being able to remotely activate the mass relay for the invasion. And one Prothean survived in stasis, and became part of the crew that eventually ended the Reapers after an estimated ''20,000'' cycles of extermination.]]
* In ''VideoGame/{{Stellaris}}'' purging will give an empire a permanent penalty to diplomacy as everyone else suspects they might be next. And if you only conquer part of an empire and purge the planets you seized the rest will dedicate their existence to revenge.
* In ''Franchise/TheElderScrolls'' series' backstory, the Atmorans, a [[BarbarianHero barbarian]] {{Precursor}} race of the [[HornyVikings Nords]], began migrating to Tamriel from the now-lost [[GrimUpNorth continent of Atmora]], landing and settling in modern day Skyrim. The [[OurElvesAreBetter Falmer (Snow Elves)]], who inhabited Skyrim, grew concerned when they started to become outnumbered by the Atmorans. While there are conflicting details regarding exactly what happened that night, the Falmer would attack and massacre the Atmoran city of Saarthal. Unfortunately, [[FounderOfTheKingdom Ysgramor]] and his sons survived. They returned to Atmora and raised an army of 500 of Atmora's greatest warriors. They returned to Skyrim and led a [[ThePurge Purge]] on the Falmer, slaughtering the majority of their population. Save for a small population at a very remote monastery, the surviving Falmer were forced to turn to their [[OurDwarvesAreDifferent Dwemer]] cousins for shelter. The Dwemer agreed to take them in, but only if the Falmer agreed to consume poisonous mushrooms to permanently blind them and essentially become EnslavedElves to the Dwemer. Following the [[RiddleForTheAges disappearance of the Dwemer]], the surviving modern Falmer are now barely sapient [[TheMorlocks Morlock]]-like creatures who continue to inhabit the Dwemer's abandoned ruins. However, by the 4th Era, the Falmer are growing more bold, venturing above ground to kidnap surface dwellers while their numbers swell beneath ground. They also seem to be regaining some of their lost sentience, forging better weapons and armor from farmed Chaurus chitin and practicing crude alchemy to create poisons from the plentiful mushrooms that grow in their underground lairs. The author of one in-game book in ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'' even believes that the Falmer may be preparing to wage war on their surface dwelling ancestral enemies, crossing over with elements of CreateYourOwnVillain and LaserGuidedKarma for the Nords.
* In ''VideoGame/XenobladeChroniclesX'', the Ganglion [[spoiler:tried to destroy humanity due to being descended from the Samaarians. This backfired ''before the genocide had even started'' as Elma had given humanity faster than light travel and warned them about the Ganglion, and although the Ganglion destroy Earth, Luxxaar is killed by Lao and the Ganglion is, for the most part, destroyed by BLADE.]]

* In ''[[Webcomic/TheOrderOfTheStick Start of Darkness]]'', [[LightIsNotGood crusading paladins]] go and wipe out multiple villages of [[AlwaysChaoticEvil goblins]] while seeking the high priest, whose God has a plan that threatens the very fabric of creation itself. In the process, they [[KnightTemplar killed every man, woman and child]] they could find, but missed two -- Redcloak and his brother. In the current story arc, Azure City has been conquered by Redcloak and his armies, and is running the human population into the ground.
** And in comic 842, while it doesn't fall under any of the variants mentioned in the main article since it does wipe out everyone V wanted dead, boy does Darth V's Familicide coming back to bite him/her in the ass. [[spoiler: The Draketooth family, guardians of the 4th Gate, were all part dragon, namely, part of the same family V used Familicide on.]]
** The reason the paladins of the Sapphire Guard chose genocide as their solution rather than simply hunting down the goblin high priest is that the high priest wears a magical artifact, the Crimson Mantle, linking his mind to the goblins' evil god the Dark One. If the high priest is killed, any other goblin can wear the Crimson Mantle and become the new high priest. Thus, the only way to end the threat forever would be to exterminate every last goblin in the world. (Destroying a divine artifact isn't really something within the power of mortals after all.) Now guess what Redcloak's new name (adopted several years after the genocide of his village) refers to.
* [[spoiler:[[GambitPileup Linda, brainwashed by the government, actually the Britjas under a false flag]]]], all from ''Webcomic/ItsWalky'', killed all the so-called "Martians" in TheSeventies. "So-called" because [[spoiler:Mars was just an outpost of an intergalactic empire]]. Of Franchise/{{Cthulhu|Mythos}}-like creatures who'd been leaving around all that [[MagicFromTechnology sufficiently advanced]] ImportedAlienPhlebotinum that drove half the comic's plots. This goes about as well as you'd expect.
* Sometime during the Dominion War in ''{{Webcomic/Terinu}}'''s past, the human rebels attempted to destroy the Varn Dominion's main power source. Said source consisting of childlike sentient beings known as the Ferin. The Terran Federation trying to both finish the job and keeping the secret from their allied races is a major plot point.
* A few centuries into the back story of ''Webcomic/ErrantStory'', the Elves discovered that some Half-Elves may go crazy and spontaneously develop inexplicable talent in destructive magic. The Elves forbade cross-breeding with Humans and organized a branch of the military to hunt down Half-Elves. They haven't been exterminated-- there are at least enough Half-Elves to populate a hidden village-- and no prophecy is involved, but one Half-Elf has absorbed a comatose Elven deity and is leading an army of the descendants of the Elves' Human bodyguards to wipe out the last surviving Elven city.
** Even better: The reason that there's just one Elven city left? They were so [[CantArgueWithElves smugly arrogant, callous and intractable]] in their attempted genocide that basically every other power group (including their erstwhile allies and pawns) basically [[ScrewYouElves told them where they could shove it. Violently]].
** Even worse: The half-elves learned absolutely nothing from this and tried to commit genocide on the elves in return, thus justifying the elves' genocidal rampage by the end of the war. Millennia later, some of the elves' erstwhile allies and some of the remaining half-elves STILL want to kill off all the elves. This ends about as well for said people as one might imagine, though the elves are less than happy with their rescuers. Probably because the elves are STILL the same genocidal jerks who caused the war in the first place, being immortal and all.

[[folder:Western Animation]]
* ''WesternAnimation/AvatarTheLastAirbender'':
** Fire Lord Sozin knew that after he left Roku to die, the Avatar would reincarnate amongst the Air Nomads. So, the Fire Nation managed to kill off the Air Nomads... except for [[TheChosenOne the one kid they were aiming for]].[[note]][[AllThereInTheManual Supplemental material]] says that one other Air Nomad turned traitor and became a citizen of the Fire Nation.[[/note]] Aang ends up stopping the Fire Nation later (though they did screw up the world and their own cultural morality pretty badly in those 100 years he was gone).
** Another complicated invocation of the trope is the Fire Nation tradition of hunting and killing dragons to prove one's mettle as a firebender (again started by [[JerkAss Fire Lord Sozin]]) which apparently pushed the species into extinction in less than 100 years, with Sozin's grandson, Iroh, acclaimed for killing the last pair. When Zuko, Sozin's great-grandson and Iroh's nephew, needs to find the original method of firebending, before it became corrupted by relying on anger, guess who the original firebenders who might have been able to help him were? [[spoiler: He ends up finding the last pair, whom Iroh had lied about killing to protect, and is judged worthy of the knowledge he seeks.]] Not to mention the extermination of the dragons likely made the war effort that much more difficult, because they wiped out their own flying, fire-breathing assets.
* Subverted in ''WesternAnimation/DrawnTogether'', where the last survivor of genocide meekly submits to the killer.
* In the third season of ''WesternAnimation/TransformersPrime'', the Decepticons begin cloning an army of Predacons. But when the prototype reveals [[ItCanThink intelligence]] and abilities [[GoneHorriblyRight beyond what was planned]], Megatron quickly decides that allowing that Predacon (who now goes by the name Predaking) to have his army would be as much a danger to the Decepticons as to their enemies. He knew, however, that this was a risk, and manipulated his foes into doing his dirty work for him. This kept Predaking's attention where Megatron wanted... Until the truth got out. While Megatron himself survived [[RoaringRampageOfRevenge the resulting violence]], many who served him were not so fortunate.