Brass Body: My clan is extinct. Because I killed them.
Essentially Self-Made Orphan on a larger level, this is when a person is responsible for the death and destruction of their entire people. Likely to be part of a Bloodbath Villain Origin, and the one who does this often turns out to be a budding Omnicidal Maniac or a Straw Nihilist. Don't be surprised if There Is Another from the group who survives and looks to settle accounts somewhere down the line.
Similar to Hunter of His Own Kind, but tends to differ on several counts, including that Hunter of His Own Kind tends to be an ongoing trope currently in effect, with few if any signs that they will ever suceed in largely wiping out their own kind. (Also, they may simply be hunting evil members of their own kind or even an Evil Counterpart Race.) Like that trope, the slayer can be portrayed as quite differing degrees of depraved, himself, depending on just how bad his people were—or in some cases even heroic, if they were really, truly irredeemably evil, monstrously inhuman or otherwise completely unsympathetic. In any case, with this trope, the person carrying out the genocide has already succeeded and whatever is left of their people, if anything, is a tiny remnant at best.
See also Sole Survivor, Last of His Kind, Antagonistic Offspring. Often overlaps with Self-Made Orphan and/or The Purge. Compare and contrast with Hunter of His Own Kind, Boomerang Bigot, Where I Was Born and Razed and Category Traitor. A subtrope of Murder in the Family.
- In Naruto, we know from the start that Sasuke's older brother Itachi did this to his clan many years ago, sparing only Sasuke. Only much later do we find out why: Itachi was under orders to do so from Konoha (mainly Danzo), as his clan was planning a coup. And even then, Itachi didn't kill most of the clan Obito did. Obito was also the one who manipulated the circumstances that led to them planning the coup in the first place, engineering their demise.
- In Samurai Champloo, soldiers of the Matsumae domain sent to arrest the Ainu warrior Okuro believe that he did this to his own clan and also killed samurai from their clan. The truth is that Okuro's clan was wiped out by a disease and he attacked the samurai because he saw them burning the village to prevent the disease from spreading rather than trying to save the people.
- Cars the Pillar Man from Part 2 of JoJo's Bizarre Adventure practically wiped out his own race when they opposed his goal of elevating their already powerful race to Ultimate Lifeform limits. He only spared his loyal follower Esidisi and two infants he would raise to become his servants.
- Eneru from One Piece destroyed his homeland, Birka, after getting his Shock and Awe powers.
- Wavess, the first major enemy of the Shonen Jump manga Stealth Symphony, proves to be this. She killed half the population of her mermaid tribe and sold the other half to the very pharmaceuticals that experimented on her and gave her power over liquid because she was angry that at how happy they were at the chance for some revenge when she was the one with the power.
- Fujimoto from Ponyo on the Cliff by the Sea aspires to this — also overlaps with Kill All Humans and Transhuman Treachery.
- During the Future Trunks' Saga in Dragon Ball Super, Future Zamasu and Goku Black, who are the same person, are revealed to have singlehandedly slaughtered all of the other Kais in the twelve universes to keep them from stopping their plan to slaughter the mortal races. Despite the fact they wanted to rid the multiverse of the mortal races to let it be a paradise for the gods, they really didn't seem to have a problem with being the only gods to enjoy it.
- Attempted in Attack on Titan. The King's Will implanted into the Founding Titan is one half of a scheme between Karl Fritz and the Tybur Clan to eventually wipe out of their own people. King Fritz implanted his Will into the Founding Titan, so that none of his successors could use its power to prevent the eventual genocide of the Eldian people. Meanwhile, the Tybur Clan ruled over Marley from the shadows while all other Eldians were thrown into concentration camps and used as military fodder. Eren presents the first opportunity in a century to escape this fate.
- Lobo the Czarnaian killed the rest of his race with a biological weapon. As a high school science project. He gave himself an A.
- Indirectly done by Marvel Comics' Impossible Man, who convinced Galactus to devour his own planet instead of Earth, killing all the Popuppians (except himself) in the process. They didn't mind.
- The ultimate goal of the somewhat terrifying Magnificent Bastard/Villain Protagonist Billy Butcher from The Boys is to kill everyone with Compound V in their system, thus ridding the world of supes altogether. It doesn't matter that Billy himself or all his best friends have been injected with Compound V, or that at this point so much of the world's population has been exposed to it that it's essentially become part of life in that world, Billy still is working towards that goal. Ultimately, he nearly goes through with it, and only the fact that he doesn't really want to kill all the people who've been unknowingly exposed to Compound V or his Morality Pet Wee Hughie stops him.
- Martian Manhunter's insane brother created a psychic plague that killed all the Martians. J'onn only survived because he did the psychic equivalent of cutting off an arm by severing his link to other Martians.
- With just three words, "No More Mutants" the mutant Scarlet Witch managed to reduce the mutant population from somewhere in the millions to little over 200. Some were depowered, some were killed (mostly due to their powers being vital to them) and the damage was not restricted to their home dimension, it was OMNIVERSAL.
- In Annihilation, Stardust gives up the last remnants of her entire race of celestial beings to Galactus to eat.
- Shakara: Cinnibar Breneka, the noble founder of the Shakara Federation, is responsible for its destruction when he united the Shakara's enemies to wipe out his brethren with a Synthetic Plague and destroy his own homeworld.
- In the Pony POV Series, it's eventually revealed that Lord Tirek came to believe that his species had become weak and soft. So his first atrocity upon getting his power was to wipe out his own kind out of disgust.
- In The Bridge, the albino Hyper Gyaos is forced to kill the rest of her kind in self defense when the scent of her wounds drives them into a bloodlust and they try to eat her.
- Late in The Man with the Iron Fists, Implacable Man mercenary Brass Body reveals that he originally was a member of yet another animal themed clan from Jungle Village, but that he wiped out his own clan years ago.
- Attempted in Who Framed Roger Rabbit which has Judge Doom trying to wipe out all the Toons and literally erase them and their home of Toon Town from the face of the Earth with "Dip" despite being a Toon himself.
- Loki attempts this in Thor, because his adopted parents let him think his species was a bunch of monsters and then admitted he was one of them at the exact wrong time. There are also "Well Done, Son!" Guy overtones of his attempting to show that he is a "true son" of Odin.
- In the Star Wars movies, the former Jedi Darth Vader played a large part in the elimination of virtually all Jedi from The Empire.
- The Elric Saga: In the short story, The Dreaming City, Elric leads an attack on Imrryr, the capital of Melnibone, of which he is the rightful emperor. The attack not only leads to the death of the city and its people, but also the one thing Elric actually wished to save from harm: Cymoril, his betrothed.
- In The Crystal Star, Hethrir, a Dark Jedi trained by Darth Vader, glassed his own homeworld and had the survivors turned into Human Popsicles in an attempt to curry favor with his master.
- In the Myst novels that reveal the backstory of the D'ni people, Veovis and A'Gaeris unleash a plague that wipes out most of the underground city's population and follows its refugees into other Ages, bringing down their civilization.
- In The Dresden Files book Changes, the half-vampire Martin is a triple agent who pulls a complex Thanatos Gambit to ensure his Red Court vampire masters will be annihilated by Harry Dresden. The motives are complex, but boil down to "My kind are too evil to let exist."
- In The Magician's Nephew, Jadis the White Witch, the Big Bad from the first The Chronicles of Narnia book, is revealed to have cast a spell that killed everyone on her world except her when she was on the edge of losing a civil war.
- A downplayed example in I Have No Mouth and I Must Scream, in which the protagonist kills all the other surviving humans; there were only five of them left anyway. Not to mention, leaving them alive was a Fate Worse than Death, which they'd been suffering for centuries.
- Doctor Who:
- The Doctor seemingly blew up his own planet during the Time War in a last ditch attempt to save the universe not only from the enemy Daleks, but also the increasingly destructive actions of his own people, the Time Lords. Thanks to the Timey-Wimey Ball this is actually Subverted. He didn't kill anyone, he simply thought he did, but actually sent the Time Lords to a pocket dimension.
- Davros arranged for the destruction of his own people, the Kaleds, by their mortal enemies, the Thals, when the former tried to stop his experiments.
- In the series closer "Journey's End" Dalek Caan manipulates the Doctor into causing the total destruction of the Daleks (for a while) after a trip through the time vortex forced him to have a Heel Realization.
- In Battlestar Galactica (1978), this is Baltar's endgame. He is a human who is a high ranking Cylon controller, and the Cylons are after the complete destruction of the humans. Note that this is a bit of a retcon from the original Battlestar Galactica movie; in that one Baltar, having betrayed humans to the Cylons in exchange for them guaranteeing the safety of his own world and his dominion over it, is summarily executed by the Cylons because their plan is to extinguish all humans.
- In Battlestar Galactica (2003), John Cavil, the oldest member of the second generation of Cylons, has committed genocide so frequently that he approaches Omnicidal Maniac territory. He not only started the war of extermination against the humans, but has wiped out more than half of his own race. He destroyed all the Daniel copies out of jealousy by poisoning their embryonic chambers as the clones were being developed. When a civil war breaks out among the Cylons, he pretends to desire a settlement, only to betray the other faction and resorts to wiping out all the Sixes, Twos, and Eights (minus Boomer) still in existence.
- Kamen Rider Drive has this in the form of Medic. Upon gaining the title of "Grim Reaper", she began silently exterminating Roidmudes who either act ruthlessly or act outside their jurisdiction. She eventually concludes that only a select few of the Roidmudes including herself and Heart should live. However, Heart stops her and reminds her that they're already a dying race with the Kamen Riders killing their kind.
- In the Ravenloft module Curse of Strahd, Strahd von Zarovich's chamberlain Rahadin pulled this twice on his own people, the Dusk Elves, at the orders of Strahd. First he betrayed his original ruler Prince Haramun in favor of Strahd andhis father Barov when their lands were conquered and was made an honorary member of the royal family in return, and then years later after Strahd's would-be-bride Patrina was stoned to death by her own people before she could marry him Rahadin was ordered to hunt down and execute every female Dusk Elf so what remained of his race would die a slow death by being unable to breed.
- While suffering from a case of Amnesiac Dissonance, Tatsumaru from the second Tenchu game virtually destroys his own clan, leaving only a few survivors, including the two main characters.
- The King of Fighters: Because Gaidel refused to take part of Goenitz's plan of resurrecting Orochi, he manipulated Gaidel's daughter Leona into her Riot of the Blood mode and had her slaughter her whole clan.
- In Runescape, the War God, Bandos, got his start as a sadistic mortal warlord. He gradually wiped out tribe after tribe. He ultimately killed the god that protected his homeworld from asteroids both to claim the god's power and out of a deliberate desire to wipe out his entire species as a testament to his glory.
- In Strider 2, Strider Hien betrayed the Striders organization to join Grandmaster Meio, and his actions led to the group's total extermination...the Sole Survivor of which was Hiryu himself, now determined to complete the group's final assignment: hunt Meio down.
- Seath the Scaleless from Dark Souls was born an abomination without the scales that granted the other dragons immortality. Out of jealousy, he betrayed his own and sided with Lord Gwyn in the war against his brethren, leading to the extinction of the Everlasting Dragons.
- In the evil ending of Infamous Second Son, Delsin returns home with his concrete powers to save the rest of the Akomish tribe, only for the tribe to reject him. Having seen his rampage through Seattle on the news, they now view him as a disgrace to the tribe, and would rather die, taking their culture with them, than be saved and owe their lives to a raging psychopath. Furious at their rejection, Delsin eagerly helps them along to their deaths by planting an Orbital Drop on the Akomish longhouse.
- Emperor Percival Tachyon from Ratchet & Clank Future: Tools of Destruction is hell-bent on killing off all Lombaxes in existence, including our protagonist, for banishing his Always Chaotic Evil race from the universe - even though he was raised by them from a hatchling despite his evil heritage.
- In the bad ending of Shantae: Half Genie Hero, Shantae is forced to destroy the corrupted genie realm, effectively committing genocide against her own people, to protect the world.
- Arcueid from Tsukihime is the last of the vampiric True Ancestors by the misfortune of having slaughtered the hundred or so of her remaining kin in a fit of berserk rage after Michael Roa Valdamjong tricked her into drinking his blood.
- In Kingdom Hearts I, this is Jafar's ultimate goal for Agrabah. After succeeding in conquering the world, capturing Jasmine, and obtaining the Magic Lamp, he makes his first wish to reveal the Keyhole, which will allow the Heartless under his command to enter and take its heart. Had Sora not arrived in time, Agrabah would've been destroyed and everyone on it killed.
- In the same game, Ursula makes a similar attempt to destroy Atlantica. Unlike Jafar, she can't find her world's Keyhole.
- In Drow Tales, Snadhya'rune, the Big Bad, deeply resents her entire family and tricks her clan into infecting themselves with demons so as to eventually ensure their horrific demise.
- In the Beldrobbaen clan, a traitor suffering from teenage angst and more than a little madness attempts this by infecting her clan with a madness inducing plague.
- In Freefall, two of the three individuals trying to destroy the half-billion fully sapient robots on the planet Jean are robots themselves. One came to believe that it was necessary for humanity's long-term well-being, regardless of what humans say on the matter; the other is constrained by the third - a Corrupt Corporate Executive literally telling it what to think.
- In Star Power the Countess killed first her mother, and then the rest of her species for what she considered to be cowardice, aka retreating from certain extinction at the hands of the empire they tried to conquer.
- Slightly Damned Mr. Moonshade is a descendant of the Guardian Moku who has murdered both Moku and everyone else descended from Moku, including his own daughter, in order to steal Moku's powers.
- In Homestuck, several examples:
- Playing Sburb triggers an apocalypse that wipes out all humans in the world except for the players (and a very few close relations).
- The same is true of Sgrub with the trolls, though due to the next event it sort of doesn't matter.
- When the Heiress Apparent leaves, her Lusus releases the Vast Glub, which kills all trolls everywhere in the universe except the Empress.
- This is the ultimate goal of OTHAR TRYGGVASEN, Gentleman Adventurer! from Girl Genius. He plans to kill all Sparks (natural-born mad scientists)... himself last. (The idea that new Sparks would keep being born after this was accomplished, since Sparks don't always have Sparky parents, seems not to occur to him.)
- 8-Bit Theater: Subverted / Downplayed. Muffin the Dragon's Evil Plan was to found an order of dragon-hunting knights, use them to kill the other dragons, take their power and wealth, and then slowly destroy the dragon-hunters. The Light Warriors, who encounter several dragons over the course of the story, point out she didn't really do a good job of it.
- BIONICLE: Once Makuta Teridax took over Mata Nui's body, one of the first things he does is destroy all surviving Makuta, except for Miserix.
- While Real Life examples of racial self-genocides are scant at best, political, cultural, and religious self-genocides have technically happened if you follow the official UN definition of genocide.
- One might see this in the histories of countries that have converted to Christianity or Islam, where followers of the old pagan religions and traditions were forced to either convert or be put to death, having their temples, monuments and written records destroyed, thereby making it a religious and cultural genocide committed by its former adherents. The Roman Empire is possibly the Ur-Example of this: at one point dedicated to the deities of Classical Mythology to the point of persecuting Christians, the Empire eventually converted to Christianity and began persecuting anyone who worshiped the old Roman gods.
- The Purge often takes the form of this. For example, Pol Pot and the Khmer Rouge government purged over a quarter of Cambodia's population, mainly targeting intellectuals and people connected to the old regime but also killing pretty much anyone else they didn't like. As another example, back to Ancient Rome, their military had an official policy called "decimation" that mixed this trope with Shoot Your Mate and used from time to time against military units accused of cowardice, mutiny, or particularly notable failure. The officers would all be executed, but then the enlisted men would draw lots — and the one man in ten who was particularly unlucky would then be beaten to death by the other nine. If the others refused to kill their former compatriot and maybe friend, all ten would be executed. Decimation was designed to make the legions more afraid of the consequences of cowardice or failure in battle than they were of the battle itself.
- The Imperial Chinese warlord Zhang Xianzhong amassed a rebellion to conquer the Sichuan region of China, and proceeded to order his soldiers to kill everyone who objected to his rule. Then, kill the inhabitants of the outlying villages. Then kill the wives of officers who had objected to the previous order. Then large groups of random civilians. Finally, he just ordered them to kill each other in front of his throne made of the severed ears and feet of his enemies. To put the effects of Zhang Xionzhong's reign of the Sichuan region into some kind of perpective, one can keep in mind that the last Ming census figure for Sichuan in 1578, more than 60 years before Zhang entered the region, gave a population of 3,102,073. By 1661, 15 years after Zhang's regin, only 16,096 adult males were registered, and Chengdu was said to have become a virtual ghost town frequented by tigers. Zhang also allegedly had a stone inscribed with an explanation of his Omnicidal Maniac tendencies:
Heaven brings forth innumerable things to nurture man.
Man has nothing good with which to recompense Heaven.
Kill. Kill. Kill. Kill. Kill. Kill. Kill.