In Ashita no Joe, Ryuhi Kin kills his father by accident when he thought he was a hungry soldier who came to his son to get him food during the Korean War. Because of this incident, he developed a fear of blood.
Kall Su of Bastard!! had killed his mother in self defense before being taken in by Dark Schneider in a story that is incredibly similar to that of Haku from Naruto.
Justified with Guts, the aptly-named main character of Berserk, who killed his abusive adoptive father in self-defense. It was either that or dying.
A much abused pre-teen girl named Rosine snapped upon being beaten by her abusive father, activated her Behelit and sacrificed both of her parents to the Godhand for her wish to become a fairy and escape from her horrid life. This led her to become the local Dark Magical Girl.
In Bleach 466, Yukio's backstory has him ruining his father's business and driving his and his mom to suicide, as revenge for their abandonment. Hitsugaya isn't impressed when Yukio tells him. There's a subversion, though: Yukio claims that he did it happily to punish them, but then Hitsugaya realizes that he's not half as remorseless as he believes; when he points it out, Yukio starts defending their memories instead, which leads to a massive Villainous Breakdown.
After Koshaku Chouno became Papillon in Busou Renkin, he decides to kill everyone in his household - except those that can tell the difference between him and his (already deceased) younger brother Jiro. Nobody succeeds, including his father.
Suzaku of Code Geass killed his father, the Prime Minister of Japan, Genbu Kururugi, during Japan's war against Britannia. He did this in order to force Japan to surrender, thus ending the bloodshed of the war and preventing Japan's total destruction, since Genbu actually was ready to have Japan destroyed rather than under Britannian rule. It worked, but the character is so horribly torn by guilt that the incident gives him Laser-Guided Amnesia for years. To make things worse, it's indicated in some of the background material that if Japan had fought to the end as Genbu wanted, that could have bought enough time for the Chinese Federation and/or the EU to intervene on Japan's behalf.
In R2 episode 21, Lelouch killed his father and mother (after spending 90% of the series trying to find out who killed her). They were trying to bring about the end of the world at the time, though.
In the light novels, it's mentioned that Blood Knight Luciano Bradley killed his abusive father at a very young age.
The Dagger Of Kamui starts with a tragic variation: The Protagonist, Jiro, is framed for the murder of his adoptive mother and sister, and forced to flee mob justice. He's rescued by a passing monk, Tenkai, who offers Jiro the chance to take revenge on the ninja who killed them. This ninja is actually Jiro's Disappeared Dad, who had rebelled against his former master. Tenkai had arranged the murder both as a trap for the rogue, and as the opening act in a Gambit Roulette revolving around making Jiro into a Tykebomb to discover the secrets that died with his father.
Dansai Bunri no Crime Edge: Yamane killed her and Houko's parents due to being influenced by by the spirit of her killing goods' original author. Houko decided to take the blame for it so Yamane wouldn't be burdened with guilt.
In the Descendants of Darkness anime, it's revealed that Muraki's half-brother Saki (who was illegitimate, through Muraki's father) killed his parents and Muraki's mother, and tried to kill Muraki himself before being shot and killed by one of the family's bodyguards. The manga has a different, more confusing take on it, which will likely never be resolved.
Dragon Ball: Goku killed his adoptive grandfather Son Gohan through accidentally stepping on him while he was in Oozaru form during the full moon. Being a child and not remembering said incident, he believes his grandfather died of natural causes. His friends deduce what happened when they see him as an Oozaru, but decide to not tell him — and neither does Son Gohan when they briefly meet thanks to Uranai Baba; Goku only learns the truth when he's an adult already, and is deeply unhappy.
In Elfen Lied, although it's not the case with any of the named Diclonii in the show, most of the diclonii kill their own parents; sometimes from fear, sometimes from the influence of their Super-Powered Evil Side.
Souther from Fist of the North Star was tricked into killing his beloved adoptive sifu, as the final stage of his training. This emotional trauma led Souther to swear off love and become a monster.
Tohru Honda of Fruits Basket originally believes she is this, believing that her not telling her mother to come home safe somehow caused her accidentnote Though this is more of a Never Got to Say Goodbye sort of thing.. Kyo Sohma, although his father is still alive, also believes himself to be this, because his curse (of being the Cat) caused his mother to commit suicide.
Gundam 00 has an interesting case: Sohran Ibrahim, the boy who would become Setsuna F. Seiei, the lead protagonist himself, shot his parents to death. In his defense, he and many other kids were brainwashed into doing so by Ali Al-Saachez to "prove their faith" to a cause Ali himself didn't even believe in, and it's definitely not something he's proud of. One reason he's more or less close to Rebellious Princess Marina Ismail is because of her similarities to his dead mother.
Andrei Smirnov of the A-Lawskills his own fatherSergei, under the mistaken impression that he was part of a coup. He only realised his horrible mistake thanks to a combination of space particles and a pep talk with his adoptive sister Marie.
In Haou Airen, Hakuron's father was an utter bastard who planned to kill him due to a prophecy. A child Hakuron managed to escape from his dad's grasp (his mother wasn't so lucky), was adopted by a Triad leader, and when he was a teenager he faed his father and killed him himself.
Higurashi no Naku Koro ni has a tragic case of this trope. In her backstory, Satoko Hojou had become insane and extremely paranoid as a result of suffering from Hinamizawa Syndrome, to the point where she perceived her own parents as a threat to her and pushed them both off a cliff to their deaths. It was essentially a twisted kind of self-defense.
Natsumi is this in her arcs. She was infected with the same Hate Plague, which caused her to kill both her parents and her grandmother.
Cars in the second part also...well, forget killing his parents, he killed his clan, save for his ally ACDC and the infant Wham and Santana. On the other hand, they were trying to kill him before he could put his Artifact of Doom to use.
In Steel Ball Run, the AU Dio is a self-made widower, marrying an elderly lady in her eighties before she died six months laters. Unlike that first instance, a lot of people suspect Dio of killing her.
Tsubasa of Kannazuki no Miko killed his abusive father in defense of his younger brother Souma.
The fifth Kara no Kyoukai movie starts with Tomoe killing his mother in self defence, after she murdered his father. Treated oddly sympathetically, despite the rather... strange circumstances that turn out to be surrounding it.
Katanagatari: Shichika is responsible for killing both his father and sister, leaving him as the last member of his clan.
Belphegor of Katekyo Hitman Reborn! is hinted to have killed his entire family besides just his brother, though this is only actually mentioned once by Bel himself as an offhand comment to someone whom he was trying to scare.
In Mobile Suit Gundam, Prince Gihren Zabi becomes The Starscream and kills his elderly father, Sovereign Degwin, when he was trying to make peace with the Federation. He doesn't get away with it, his Evil Genius sister Kycilia offs him soon, on the grounds of him being a parricidal murderer who would've been executed anyway.
In Monster, Johan kills several sets of adoptive parents from a very young age onwards. And he kills his sister Anna's adoptive parents, too.
Narutaru has three examples. First, Hiroko "Hiro-chan" Kaizuka kills her parents with her newly-acquired Mon after certainfactors drive her to insanity - and said parents' emotional abuse (at least from Mr. Kaizuka's side) is just the straw that breaks the camel's back for her. Secondly, in the manga only, it's suggested that Naozumi Sudomight be responsible for the "disappearance" of his parents and older brother, though his true involvement in the matter is left ambiguous. There's also how Komori neglected his sick mother until she starved to death, though after a certain point it's difficult to tell whether he had been doing so for very long before he died.
Itachi Uchiha killed everyone in his clan except for Sasuke. A bit of a twist, since he was following the orders of his government to stop the Uchiha from committing a coup d'etat that might have resulted in another devastating world war; in exchange, his superiors agreed to spare Sasuke. In fact, Itachi's entire Start of Darkness flashback from relatively early in the series looks very different after the revelation, when you realize that his emotional rollercoaster and remarks like 'I've given up on this hopeless clan!' aren't actually budding psychosis— they're a soldier struggling to find sufficient reason to reject unconscionable orders, and failing. A later flashback even shows that he really didn't want to do it, and was crying as he massacred his family. And Fugaku and Mikoto Uchiha took their upcoming deaths calmly, basically telling Itachi "you know, it really sucks that thingswent like this, but go ahead since you've got orders and there is no other choice for you. We won't hold it against you. And we love you."
A partial example is Haku: His father killed his mother once he found out about their bloodline limit, and when he tried to kill Haku, Haku accidentally killed his father in self-defense out of fear.
The Filler Villain Shiranami killed his own father in an attempt to obtain the Dangerous Forbidden Technique which his father had been protecting just for the money it could get, and cheerfully boasts about the act.
Noir. Mafia Princess Lady Silvana, aka the Intoccabile, killed her father for violating the Mafia's code of silence, and when she returns from her banishment kills her grandfather (who banished her) as well. These acts cause Silvana to be regarded with awe by the other mafiosi, and professional assassin Mireille Bouquet is terrified of her.
Mireille killed her uncle Claude, who had been her surrogate father ever since her parents and older brother were killed by little Kirika.
In the final episode, Kirika arguably fits this trope, when she kills Altena, who is the closest thing to a mother figure that she's ever knowingly had.
Also, after Yukishiro Tomoe's death, her little brother Enishi is adopted by a wealthy Chinese family who find him in a gutter after he flees Japan. He kills them, both for the huge sum of money they had and because he simply couldn't stand anyone having a happy life after losing his own.
Implied of the Ax-Crazy Chiri Kitsu in one episode of Sayonara, Zetsubou-Sensei. Itoshiki-sensei is killed and she "replaces" him with a small doll to cover up the crime. She quickly becomes paranoid about the rest of the class and they are replaced by dolls as well. While everyone is shown to actually be hiding safely under the school, it makes you wonder when the next scene appears to be Chiri happily telling her parents about her day- and then you see she is addressing dolls...
One of the arcs in Shigofumi involved a highschool-age girl who had been forced into pornography by her father. It's unknown what happened to her mom. But when her dad suggested to her that he wanted to get her little sister into the business, she killed him. You could hardly shed any tears for the dad, though.
A pretty convoluted case is shown in Tantei Gakuen Q. The widow Hanayo Ichinose fakes her death and uses the insurance money to rebuild her business, then gets plastic surgery and tries to get closer to her family (who don't know she's still alive) under the disguise of a Phony Psychic. Her sons Akihiko and Kunihiko, however, mistakenly think that the strange woman who tries to worm her way in their lives is an accomplice of their Evil Aunt Sachiyo, a greedy Smug Snake who wants to get the custody of their little sister Kaoru since she's the rightful heiress to what's left of to the family fortune.. so they murder Hanayo without knowing who she really is, in a desperate bid to save poor Kaoru from Sachiyo's machinations. What follows is heartbreaking.
Dlanor A. Knox killed her own father after he violated the Knox Decalogue. Afterward, she stopped aging.
Also, in one arc George Ushiromiya kills his mother Eva. It was mostly in self-defense when her Superpowered Evil Side Eva-Beatrice came out in the middle of a heated discussion in regards to her Parental Marriage Veto, though.
Tasha Godspell's sister in Witch Hunter killed their father soon after awakening as a witch, an event that drove her insane. She also killed Tasha's mentor, who was like another mother to Tasha, in a fit of jealousy.
Variation: In X, Seishirou Sakurazuka killed his mother Setsuka not because of hate, but simply because that was the main requirement to become the Sakurazukamori. In fact, Setsuka knew it'd be like that ever since she had him, and she even got to Go Out with a Smile in her son's arms while telling him that he would die in the same way.
Bruce Wayne's childhood friend Thomas Elliot tried to kill his parents at a young age in order to inherit their riches and because his father was an abusive monster and his mother a simpering money hungry lunatic. He only succeeded in killing his father, and, to avoid suspicion, didn't try again, only truly being orphaned when he smothered his raving senile mother in a fit of anger. This left him with a bitter hatred of Bruce, who tragically lost his parents soon after Tommy tried to kill his. Later on in his life, he joins the Riddler (who discovered that Bruce was Batman on a vendetta against him, feeling that, not only did Bruce get the riches Tommy wanted, but that he was wasting those riches as well. Predictably, his vendetta eventually causes him to lose everything and become the full time Super Villain Hush.
Black Mask killed his parents in a fire to inherit their business and fortune. Unfortunately, he was a lousy businessman and when he tried to burn down the factory to cover his tracks, he wound up with the facial injury that gave him his villain name. He was a lot better at being Ax-Crazy than a businessman anyways.
And the Penguin murdered his father (along with his brothers) in the miniseries Penguin: Pain and Prejudice so he could be alone with his mother, the only person who loved him.
A one-off character in the debut issue of Gotham Knights is a child that kills his parents.
Subverted in the Season 9 Buffy the Vampire Slayer comics. Faith is made so angry that she chokes and almost kills her father, but was stopped by Angel.
Misfit is also technically a Selfmade Orphan, though she did it accidentally. When her apartment building caught on fire she tried to "bounce" away with her mother and little brother. That is how she found out that any living thing she bounces with her dies en route. She clings desperately to Barbara Gordon and the Birds of Prey because she needs both a surrogate mother figure and the opportunity to atone for accidentally killing her family.
Subverted in Cable & Deadpool. The title characters are at a bar discussing their less-than-stellar childhoods over beer (well, only Deadpool's drinking - Cable's temporarily regressed to his teens). Deadpool's brief flashbacks show his mother's death led to his dad becoming strict bordering on abusive, and he may have shot him. At the end of the issue, we get the full story - it was one of the "wrong crowd" Wade had fallen in with, and he was genuinely horrified.
Evan McCulloch, the second Mirror Master from The Flash series. He was an orphan and end up killing his father by accident in his job as a hit-man. As a result, his mother committed suicide. Another Rogue, Captain Cold, confronted his abusive father but couldn't bring himself to kill the man... so he had Heat Wave do it.
Hellboy's Liz Sherman became one accidentally, after a Superpower Meltdown of hers created a fire that destroyed a city block (among the fatalities were her parents and brother).
Another rare heroic example: Before Bruce Banner became the Hulk, he semi-accidentally killed his abusive father, Brian. In their final confrontation, Bruce lashed out as Brian got ready to attack him, sending Brian crashing into the gravestone of Bruce's mother and cracking his skull.
It was self defense however, since his father was trying to kill him and he had killed Banner's mother.
It's implied in several stories that the Post-CrisisLex Luthor murdered his own parents when he was just a child.
"Hah! That's rich. I'm the last Czarnian. *Aside* I fragged the rest of the planet for my high school science project. Gave myself an A."
In Locke & Key, Ellie Whedon comes really, really close to pushing her horrible mother off a cliff after she puts a cigarette out on her son's neck, but can't go through with it. However, the evil spirit she unwittingly unleashes a few pages later has no such hesitation.
Loki created a Stable Time Loop to ensure his biological parents would die in battle so he would be adopted by the Asgardians.
The notorious 1954 EC Comics story "The Orphan" (featured in the page image) featured a little girl who kills her abusive father and then frames her neglectful mother and her lover for the murder (resulting in their on-panel execution in the electric chair).
In the ROM comic, there was a half-breed offspring of a human and a Dire Wraith, calling itself Hybrid, who was a true monster, murdering both parents by magically 'aging' them and then impaling his father with a pitchfork. It might not be entirely Hybrid's fault - he was raised by the uber-evil Dire Wraiths, the ultimate form of child abuse. Still, he was as close to pure, self-consciously intentional evil as is likely to be possible.
Rare heroic example: the Runaways were formed when they found out that their parents were a band of supervillains called the Pride, and after initially just trying to avoid their parents, they ended up having to battle them, resulting in the death of all of their parents and the one member of their own who had remained loyal to the Pride. Subverted somewhat since they never actually intended to kill them.
This tradition continued with the later Runaways - while Victor's mother was killed by his father (who happened to be Ultron), Xavin was inadvertently responsible for his parents' deaths, as his attempt to marry Karolina and force peace between their people ended up re-igniting the war between them, resulting in Xavin's homeworld being destroyed, and Klara is effectively an orphan by virtue of outliving both of her parents thanks to her traveling forward to the 21st century.
Catman from Secret Six is technically a Self Made Orphan, although he only shot his mother accidentally because his father pointed the shotgun at her while Thomas was attempting to shoot him. He did finish the job with a machete in the dad's stomach, though.
Warlock of the New Mutants is a member of the Technarchy, a technological race where being a Self Made Orphan is the standard - adulthood was confered after you killed your "Siredam". Warlock fled because A) his "mutation" was the realization that this was a strange way of doing things and B) the fact that his father, The Magus, can casually tear apart suns.
Rahne Sinclaire, aka Wolfsbane of X-Factor and the X-Men, did this to her father, when the brainwashing he had put her under kicked in and caused her to maul him to death before devouring his corpse.
In X-Wing: The Phantom Affair, Loka Hask, the Ax-Crazy psycho who killed Wedge Antilles' parents, comments that Wedge should thank him for it, then goes on to muse that he wishes he had had someone willing to do that for him when he was a boy, but no, he had to do it himself.
While he has a Multiple Choice Past, one detail that Bullseye keeps bringing up consistently is that he murdered his parents, who were abusive (although the circumstances are sketchy).
He offed his dad in Dark Reign: Hawkeye, long after he became a supervillain. Not that he didn't try before though.
Huntress does this when she arranges the murder of her father at the end of Cry for Blood. In this case, this was more anti-heroic than outright evil, since her father was a vicious gangster who had ordered the murder of the rest of her family and was trying to blackmail her into joining his gang as an assassin.
Judge Dredd: Judge Death murdered his own family when he was still human and known as Sidney. He first made a failed attempt to kill his sister for telling on him for torturing the family dog. He later reported his deranged father, a Depraved Dentist and Serial Killer, to the Judges to further his own career and carried out the execution himself. As a registered Judge years later, he hunted down his mother and sister after they had gone into hiding, shooting his crippled sister in the face and throwing his mother off a cliff.
The Dark Lords Ascendant: Zhang is revealed to have killed his father to prevent him from sending an assassin after him when he struck out on his own with some very dangerous martial arts techniques.
Harveste, who was living with abusive relatives after his loving parents died protecting him, killed his legal guardians and his cousin, effectively re-orphaning himself at the age of five.
Not anymore. While it is possible he still killed his family, after the rewrite, he just simply killed his entire planet.
In The North Remembers, Ramsay Bolton, during Stannis Baratheon's attack on Winterfell, finally loses it and kills his father Roose Bolton with his flaying knife. He takes him off guard as he's shouting orders to his men, and drags the knife deep down into his spine and through his throat. When the castle explodes, he finds the corpse of his father horribly mutilated from all the rubble, and pees on it as final insult. To most characters, this would be seen as a Moral Event Horizon, but considering how Roose had betrayed and murdered his own King, desecrating his body with the Freys, it's more of a Karmic Death. Fat Walda Frey, who is Ramsay's step-mother, also meets a gruesome end as Ramsay beats her to death with a jagged rock.
In The Prayer Warriors, Percy Jackson, having joined the Prayer Warriors on their quest to kill the Greek Gods, kills Zeus after declaring that he is not his father- God is- in order to avoid committing the sin of patricide. Canonically, Poseidon is Percy's father, but Percy kills him later that chapter, so this still counts any way you look at it. Thalia, Zeus' daughter, helps kill Zeus in a flashback to the retconned version of the scene.
In manycanons of Troll Cops, Tavros, aka the Nefarious and Notorious Mr. Pupa, did this as the first of his many heinous criminal acts.
Lord Shen in Kung Fu Panda 2 is an indirect example. He massacred a village of pandas and was banished by his parents as a result. According to the Soothsayer, the grief of sending him away caused them to die from despair.
In Monsters vs. Aliens Gallaxhar mentions that he wiped out his entire planet starting with his parents.
We think. All we know is he found out they were (tube closes), and that he went on the road with a giant (tube closes), a relationship that ended when she (tube closes).
Alien: Resurrection. The Newborn, immediately after being born, inspects the Queen Alien and kills her.
Diane in Angel Face, though she only intended to murder her stepmother through Vehicular Sabotage, and not her father as well.
Catherine Trammell from the Basic Instinct movies may have killed her parents after writing a book detailing her plan to do so, then used, "right, I wrote out this plan for killing my parents, published it in a book, then did it— I'd have to be crazy to do that" as a defense. Whether she actually did murder her parents or not is not actually stated, though several characters express their opinions that she did.
Roy Batty in Blade Runner, with the interesting twist that Tyrell, a genetic engineer is both a fatherlike and a godlike figure.
Michael Carter, the archvillain of the Aussie horror flick Feed, smothered his obese mother when he was a child. He's locked into a cycle of repeating the same murder as an adult.
It's implied Ginger and Brigitte did this to their abusive parents in Ginger Snaps Back The Beginning. When they come upon an outpost, Ginger says that their parents drowned - which is soon revealed to the audience to be bullshit. However, when talking privately with Brigitte, Ginger still alludes to their parents being dead, so one wonders why she had to lie about it before. Add in the casual references to them having been beaten before, and the fact that for some reason, they're traveling on their own during winter at the start of the movie, and the fact that Ginger, at least, always had some sociopathic tendencies, and... Yeah.
In Hellraiser III: Hell On Earth, Pinhead reveals that Monroe killed his own parents with the same gun he tries to use on the pillarized Pinhead.
In the second The Human Centipede movie the Villain Protagonist's mom tries to kill him but he wasn't in his bed at the time. A few minutes later he in turn kills her then sets her bashed in corpse at the table and continues his dinner like nothing happened.
Edgler Vess in the film IntensityLampshades the Freudian Excuse when he tells the protagonist that his parents were most loving, caring people that could have ever wanted... but he killed them anyway.
While he didn't kill them, the titular child character of the movie Joshua drove his mother crazy until she was committed and drove his father paranoid until he was arrested, essentially making himself an orphan. All so that he could be adopted by his uncle, who he liked better.
In the Brian Bosworth movie Stone Cold, the villain tells one of his soon-to-be-murder victims:
Chains: You know, at moments like this I think of my father's last words, which were... "Don't, son, that gun is loaded!"
Double subverted in Thor when Loki kills his biological father Laufey while declaring himself the son of Odin. So it looks like he's going to kill his adoptive father in an attempt to appeal to his biological father, but then he kills his biological father in a (completely misguided) attempt to appeal to his adoptive father. Wow.
Happens more than once in Village of the Damned. Specially notorius in the 1995 version, where Mara, the ringleader of the Creepy Children, first telepathically forces her mother Barbara to put her hand inside a boiling pot, and then uses hee Psychic Powers again to make her throw herself off a cliff.
Enforced in Death Warmed Up. Dr. Howell wants to get rid of his partner Prof. Tucker, whom he sees as an obstacle for his ambitions of creating a way to prolong life. He proceeds to brainwash his son (and the film's protagonist) Michael to kill him and his wife. Michael ends up in a mental facility, and Dr. Howell enjoys a productive career.
There's an old Jewish story that's a good way to introduce the concept of chutzpah: a man convicted of murdering his parents begs the court for clemency on the grounds that he's an orphan.
In the Alex Rider book Eagle Strike, the villain Damian Cray lost his parents in an accident when a car fell on them from a falling structure. It wasn't an accident.
The dwarf Tyrion Lannister murders his father Tywin, who had always hated him for being born deformed after his mother died in childbirth. Tyrion does that to punish Tywin for having destroyed his first marriage, by forcing Jaime to lie about Tyrion's wife being a prostitute.
Although never actually stated outright, quite a few hints are dropped that this is exactly what Gregor Clegane is. And, that it supplies one of the possible reasons why his brother Sandor bailed when he did: he saw the writing on the wall.
Lord Eon Hunter's sudden death leads people to blame his eldest son Gilwood for the murder. He wasn't the culprit, though. All this time, it was Harlan, the third son, who might also be planning to murder his older brothers so he could be Lord of Longbow.
In The Bad Place, by Dean Koontz, Frank killed his single biological parent, a hermaphrodite who self-impregnated. This provides a major conflict, as a sibling of said Self-Made Orphan wishes to avenge that act.
The title character of Carrie killed her mother in self-defense as her mother was trying to kill her (at least in the original novel, Carrie's father died in a work-related accident before his daughter's birth).
Semi-subverted in Coraline. The Other Mother has put her Mother to to grave, "And when she tries to get out, I put her back in". So the Mother of Other Mother isn't exactly dead, by for all intents and purposes, she is.
In The Dark Tower series, Roland Deschain accidentally shot his mother dead.
Harry Dresden killed his own foster father and mentor Justin Dumorne. Justified, since Justin was an evil Warlock who tried to enthrall Harry and his foster sister Elaine and had already sicced the Outsider He-Who-Walks-Behind on him. If Harry hadn't killed Justin, Justin would have eventually hunted down Harry and kill/enthralled him. Unfortunately, Harry broke one of the Laws of Magic when he used magic to kill Justin, putting Harry on the White Council's blacklist (he would have been straight up executed if a Councilmember hadn't put his own life on the line for him) and making Harry permanently at risk of falling into The Dark Side.
One of the first things Luke does in Duumvirate is this.
In Harry Potter and the Goblet of Fire, we learn that Voldemort murdered his father and grandparents as soon as he discovered they were Muggles, and not the Wizards he imagined. And that his father abandoned him and his mother while she was pregnant after she stopped feeding him the Love Potion that had kept him there and he came to his senses.
At the end of the same book, we learn that Barty Crouch Jr. murdered his father. Then transfigured his body into a bone and buried it.]] Barty makes much of how both he and Voldemort had very disappointing fathers and the pleasure of killing those fathers. He also seems to regard Voldemort as a father substitute.
This is the reason why Leo is initially afraid of his fire powers: when he was a kid, Gaia visited the workshop where he and his single mother were, with the firm intention of preventing Leo from becoming a powerful enemy; Leo used his powers to try and protect his mother, but lost control and started a fire, accidentally killing her instead. He still has his father, but since he's the god Hephaestus whom Leo only met at 15...
Hazel killed her mother and herself to stop Gaea from raising Alcyoneus back in 1942.
Getting Your Parents Shot Dead In Front of Your Eyes At first, this might seem like a strange tactic, but if it was good enough to start you know who on one of the most successful crimefighting careers of all time, then it's certainly an avenue worth exploring!
Crake in Oryx and Crake by Margaret Atwood is implied to have killed his uncle and possibly his mother, too (his father was killed (executed) while Crake was still a kid, so this leaves him an orphan).
Dillon Cole of Scorpion Shards accidentally drove his parents insane and eventually killed them before he realized that his mere touch could break minds.
Beorn from The Shattered World is an inversion, whose parents paid for him to be made a werebear when he was very young, not realizing it wouldn't manifest until puberty. Upon his first transformation, he stumbled home and was mistaken for a genuine bear; terrified, his parents barricaded themselves inside their farmhouse, only to perish when Beorn's panicked battering against the walls tipped over an oil lamp and set the place on fire.
In Slan Hunter, Jem Lorry murders his father when he learns the truth about his birth, and to ensure that the story will never be revealed.
In Ray Bradbury's short story "The Small Assassin," a baby kills its parents.
Palpatine was revealed to have murdered his parents and siblings when he was a late teenager in the novel Star Wars: Darth Plagueis. It's also implied that he desired to murder his father, at the very least, ever since he was a baby.
In the second book it's revealed that she killed both her parents. Her mother tried to kill her when she started developing the powers of a Radiant, and she killed her in self defense. Her father allowed others to believe he did it, and became an abusive drunk. She poisoned him after he really did kill his second wife and was beating her brother to death, then strangled him when the poison failed to finish him off.
Lois Lowry's The Willoughbys has the children encourage their extremely indifferent parents to go on a long vacation, hoping they'll be killed. Turns out later that's just what happens though it takes several attempts. Actually the children themselves don't have to do anything at all; their parents just seem to love taking risky chances.
In 'Interesting Times, it's offhandedly mentioned that Lord Hong's rise to Evil Chancellor involved six deaths - the last one being his father. At least he died happy that his son was carrying on a family tradition.
Treated in a bizarrely humorous way after Wesley shoots his father because his father was threatening Fred though it was actually a robot shapeshifter. Wesley was sure it was him, though, and that he would really do such a thing. Angel tries to comfort him, but it doesn't help. The characters bring up both Angelus killing his parents as a vampire and Spike killing his mother.
Angel: You know, I killed my father. It was one of the first things I did after becoming a vampire.
Wesley: I hardly see that's the same thing.
Angel: You're right, dunno why I brought it up.
Spike: Heard you offed your dad. You know I killed my mum, well I mean I'd already killed her but then she tried to shag me so I had to (mimes staking).
Wesley: Thank you, I really don't need any more comforting.
(later, again. Wesley is in his office, Fred walks in)
Wesley: If you're here to tell me about how you murdered your parents...
Fred's parents are both alive, and Wesley knew it perfectly well. Not only that, but they are the best darn parents in Texas, and until Fred dies it's probably the happiest family in the Buffyverse, so the situation is completely unlike Angel, Spike or Wesley.
Angel: "My parents were great. Tasted a lot like chicken."
Battlestar Galactica is a semi-example. The Cylons consider humans to be their parents and claim that they have to die for Cylons to reach their potential. So Cylons tried to become a Self-Made Orphan. It did not work well.
Every member of Prince Edmund's Quirky Miniboss Squad, the Black Seal, in the first series finale of Blackadder, apart from Edmund himself, but including The Hawk. Edmund does plan on exiling and imprisoning his family though were he successful in taking power.
Several Criminal Minds unsubs have done this. The most prominent examples are Frank (who killed his own mother and never knew his own father), The Reaper aka George Foyet and Billy Flynn (who shot his own mother in what he saw as an act of mercy).
In one sketch on Dave Allen At Large, a priest knocks on the door of a house, and a little girl answers. The priest says, "I'm collecting for the orphanage." The little girl says, "Hold on a moment," and disappears inside. Two gunshots are heard. The little girl returns and says, "I'm ready."
Averted and parodied in the first episode of Dexter, whose protagonist/narrator is a serial killer, when he explains in a narrative that both his parents are dead, immediately adding "I didn't kill them. Honest." It is revealed in the second season that Dexter actually inadvertently drove his father to suicide, much to Dexter's surprise.
Also, Brian, Dexter's brother (also a serial killer), offed their biological father.
Day Break: Hitman Miguel Dominguez was originally locked up for killing his own parents. It's later revealed that he did this to protect his sister from their abusive father.
It's also pretty likely that the Doctor killed his parents at the end of the Last Great Time War, although we don't really know whether or not his parents were still alive when he wiped out the Time Lords. Word of God from Russell T Davies is of the opinion the Doctor killed his mother when he ended the Time War. Given that dialogue in The End of Time reveals Time Lords were being killed and resurrected repeatedly during the War, this may be viewed as something of a release.
The Toclafane killed millions of their ancestors before their own birth, thanks to a "paradox machine" holding the Grandfather Paradox at bay.
In Game of ThronesTyrion Lannister caused the death of both of his parents; his mother died while giving birth to him, and as an adult, he murdered his father, Tywin.
Sylar on Heroes killed his mother semi-accidentally, in the fight after she tried to stab him with a pair of dressmaking scissors.
Peter Petrelli attempted to kill his pop Arthur. He failed, but his attempt was finished by Sylar, who'd been suckered into believing that Arthur was his father as well.
Narrowly subverted in Shades of Gray when Sylar tracks down his father, Samson Gray. Samson seems indifferent when he meets Sylar, and when Sylar announces his intentions to kill him, he reveals he is already dying from cancer. Samson also reveals he has a power similar to Sylar's, including an acquired ability that paralyzes a person as if they were drugged. He also shares knowledge of Sylar's methodology, picking easy, helpless targets rather than going after "big game." When Samson witnesses Sylar heal instantly after accidentally cutting himself, he tries to take the ability from Sylar by paralyzing him. Sylar, however, manages to override it. Samson points out that taking his ability will not harm him as he can heal, but Sylar says he doesn't wish for his father to have such a power, and decides to leave. Samson begs Sylar to kill him, but Sylar says his cancerwill eventually do so anyway, and leaves.
Done on Law & Order original flavor at least once; the girl in question even received a college scholarship. (The admissions board had nicknamed her "Little Orphan Annie.") She was seriously disturbed and committed another murder. A key part of getting her for the latest murder was charging her with fraud for accepting the scholarship under false pretenses.
Parker from Leverage certainly seems to be a case. In flashback, we saw her having a favored toy taken away by her (it's assumed) biological father. Next scene shows her holding the toy while walking down the driveway. Then the house explodes.
Benjamin Linus, the Big Bad of LOST, may have lost his mother to perfectly innocent Death by Childbirth, but he hated the resentment from his father so much that he killed him and the rest of the Dhama initiative with a painful-looking nerve gas.
Ben: You know, I've missed her too. Maybe as much as you have. But the difference is, for as long as I can remember, I've had to put up with you. And doing that required a tremendous amount of patience. Goodbye, Dad.
Also, Kate killed her step-father, who then turned out to have been her birth father, for abusing her and her mother.
And depending on how you look at it, when Locke forced Sawyer to kill Locke's father.
Let's be fair — Locke didn't force Sawyer to do it as much as he manipulated him into doing it. It looked like Sawyer was going to pass on killing Cooper, until Cooper, in a boast about his long career as a con man, admitted to using the name "Tom Sawyer" during a previous con. Oops...
Sawyer symbolically played this trope straight, since Cooper was the con man who destroyed Sawyer's family, which led Sawyer to a life in the same business.
In the Masters Of Horror episode "Imprint", the disfigured prostitute tells Christopher how she beat her father to death after he raped her when she was still a child.
Morgana on Merlin-her mother and the man she looked to as a father and believed for a long time was her father were already dead, but she gave Agravaine the amulet to kill the wounded Uther-her birth father.
Once Upon a Time: Regina killed her father in order to enact her curse. Her mother survived longer, but Regina was manipulated into killing her in Season 2. By Snow. Season two shows that Red killed her mother, though that was an accident.
Also in Supernatural, Bela is revealed to have killed both her parents by making a deal with the demon Lilith for them to meet with an accident. The other characters are allowed to believe it was for the insurance money, while the audience is shown scenes that strongly imply her father sexually abused her. "They were lovely people."
The season 2 (and perhaps series) final of V-2009 version “Mothers Day” has two examples of daughters killing their parents
After a Hope Spot which saw Diana take power back from her evil child and declare an era of peace with humans. Anna then returned claiming that she now understand human emotion like love and caring. However she then snuck up behind her mom and impales her with her tail cementing her status as queen.
The other was even more heartbreaking Papa Wolf Ryan was finally reunited with hybrid daughter Amy who Anna had been holding hostage this season to make him work for her. However in his absents she has become an Enfant Terrible and the little girl strangles and kills her father when he tried to save her and declared her loyalty to Anna.
Lisa almost became one in the same episode as the fifth column used her as a Decoy Damsel to lure her Big Bad mother out so she could stab her in the back and end the war. However the Manipulative Bitch convinced her that she had changed her ways and now cared about her and her To Dumb To Live daughter actually believed it. After murdering Diana Anna even boast about how she manipulated her child telling her “now that is how you kill your mother”
In The X-Files episode Eve two girls who appear to be identical twins who live on opposite sides of the country kill their fathers at the same time. It turns out the two girls are part of a cloning project that was originally carried out by the government but is now being continued by another one the clones. The clone adult that created the two girls wasn't behind the murders...the little girls were just evil.
Aerosmith's song "Janie's Got a Gun". She shoots her dad because of the abuse he inflicted on her.
Dir En Grey's song "Berry" tells the story of a nine-year-old girl who gets sick of her parents abusing her, takes her father's gun, and shoots them. If that's not disturbing enough, the girl's favorite food is jam on bread, and the blood her parents shed is referred to as raspberry jam.
Jim Morrison fantasized about killing his father (and also knocking off Brother and Sister Morrison for good measure) in the 1967 performance piece "The End" (oh yeah, and then he raped his mother). It was later parodied by Meat Loaf and Jim Steinman in 1993's "Wasted Youth".
Ira Gershwin's "The Saga of Jenny" starts with the accidental deaths of the protagonist's parents(and siblings);
Jenny made her mind up when she was three
She herself was going to trim the Christmas tree
Christmas Eve she lit the candles, tossed the tapers away
Little Jenny was an orphan on Christmas day
Tom Lehrer's song The Irish Ballad details the life of one of these:
About a maid I'll sing a song who didn't have her family long
not only did she do them wrong, she did every one of them in..
Older Than Feudalism: The Greek myth of Oedipus has him killing his father, without recognizing him, and after he's raised by adoptive parents who don't tell him he's adopted. He's indirectly responsible for mother's death when the revelation of their Surprise Incest drove her to suicide.
Greek gods love to do this as well: Uranus was overthrown by Cronus who was overthrown by Zeus.
WWE's The Undertakermay be a self-made orphan, or may not be. All we really know is that his parents died in a fire at the funeral home they owned and operated. At various points, we've been told that he set it by accident, he set it on purpose, his half-brother Kane set it, etc. It's all very confusing and pointless.
Then again, this was during Taker's Ministry Of Darknessphase, when he was allied with Paul Bearer again, so there's definitely a hint of ambiguity/unreliability as to who did what. For we know, Bearer could've torched the home.
This was during Vince Russo's run as booker, and he loves Shocking Swerves, even if they produce nonsensical, incoherent, unresolved storylines.
Vince Russo or not the backstory of both Undertaker and Kane can be easily considered a complete mess
In the Champions adventure "The Coriolis Effect," the villainess murdered her own parents by turning them into pools of slime.
Which is also the typical explanation of chutzpah in Jewish lore.
In Electra and TheLibationBearers in TheOresteia, Orestes enacts vengeance against his mother Chytaimnestra and step-father Aigisthos for their murder of his father Agammemnon. Though Electra doesn't actually wield the blade, she is guilty too.
In the Roman Comedy Pseudolus, the Pimp Ballio claims to have beaten and killed his parents 'to save their Keep'.
In the play The Revengers' Comedies, the Ax-CrazyClingy Jealous Girl who acts as a Poisonous Friend to the protagonist is strongly implied to have started the fire that killed her parents when she was eleven because they did something minor to displease her.
Played cruelly with Miles Edgeworth thinking for fifteen years that he accidentally killed his father Gregory and having constant nightmares about it. Subverted, in that it was proven that he was wrong.
In Baldur's Gate II, Valygar, whose family had been long-plagued by necromancy practice, destroyed his parents after his mother raised his father from the dead as a zombie, unwilling to accept his death, and then later joined him in undeath.
In Bioshock 2, depending on the players actions Eleanor will either save or drown her mother.
Deconstructed in the canon route of Blaze Union, where for practical and symbolic reasons, Gulcasa must kill hisMissing Mom, and she's the one who bullies him into doing it. He does not want to, but kills her anyway because by that point he has no choice if he actually wants the power to protect his loved ones. She doesn't seem to hold it against him, but this event (among others) leaves him badly messed-up for quite some time.
Additionally, Route B, starring Aegina. Ordene wouldn't have died if he hadn't refused treatment. Using Aegina for this is actually very practical, gameplay-wise, as Ordene will not use Crusade on her.
Clive Barker's Undying: Ambrose beats his father to death with a pool cue, tired of him meddling in his affairs.
In Dirge of Cerberus, one of the games in the Final Fantasy VII metaseries, Nero the Sable, one of the Tsviets, inadvertently sent his own birthmother into another dimension while she was giving birth to him due to his powers, which also acted as the reason why Shinra bound his arms as well as presumably limited his overall power.
Adell in Disgaea 2 is forced to Mercy Kill his Brainwashed and Crazy blood-parents (by their own request) near the last few levels of the game, without even knowing who they are. What's worse is that it's heavily implied that his adoptive mother was planning to tell him who his birth parents were after the end of the game. Now that's going to be an uncomfortable conversation...
In Fatal Fury, Wolfgang Krauser killed his father in a Duel to the Death to become the Earl of Strolheim. He honors his father once a year by playing the old man's favorite music in his organ.
In Final Fantasy X, Seymour kills his own father before the game starts. The reason why is because his father had him and his mother exiled after several Guado, in a case of Fantastic Racism, decried the Unholy Matrimony. Guado's father's statements in the sphere indicated that he accepted his fate fully as atonation for this sin.
The Big Bad of Fire EmblemPath of Radiance, King Ashnard, is revealed to have killed not only his parents but his entire family. You see, he was pretty far back in the line of succession, so if he wanted to become king, some pruning of the family tree was required...
In Radiant Dawnan ending sequence only available on a New Game+ implies that Soren, a mandatory recruit who was instrumental to Ashnard's defeat and death, was Ashnard's son. The irony.
In Fire Emblem: The Sacred Stones by putting Ross in the range of berserk staff you can potentially have him kill his Garcia, his father. Whoopsie.
Also, for major Video Game Cruelty Potential, in both halves you can have some of your own units kill their Archnemesis Dads: Tailto (daughter of Duke Reptor) and Lex (son of the aforementioned Duke Langobalt) for the first part, either Johan or Johalvier (sons of King Danan) in the second.
In Fire Emblem: Sword of Seals, after numerous attempts on his own life from his father, King Desmond, Zephiel decides to turn the tables. He fakes his own death, then at his funeral, when Desmond opens the coffin to check on his son, Zephiel stabs him dead on the spot.
In God of War, Kratos' mother's note in Hades confirms her death, and the ending of the game has him slaying his father, Zeus.
In Left 4 Dead, Zoey had to kill her own father to prevent him from turning into a zombie after he had been bitten by his zombiefied ex-wife. Turns out later that Zoey is immune, something that is inherited to females from the father, meaning that her father was also immune to the infection and would have survived anyway. When she realizes this, she breaks into tears for having killed him when he would avoid zombiefication completely.
Maya from Legaia 2: Duel Saga, accidentally killed both her parents at a young age when she lost control of her magical powers. The event left her mute, but she gets over it later.
Wrex from Mass Effect is from the Krogan, an entire race of Blood Knights. However, after the Krogan rebellion, the Council more or less sterilized his entire race; their birthrate became so low, they are slowly going extinctnote The details of this get fudged a bit in Mass Effect 2. The fertility rate is set to 1 in 1,000 to compensate for the Krogan being catapulted into the stars (they were needed for the war against the Rachni). It's not an attempt at extinction so much as an attempt to prevent a Baby Boom of epic proportions, resulting in the Krogan trying to wage war on the universe. But they're Blood Knights, after all, so they still tend to get themselves killed at alarming rates.... Wrex's father, the leader of their clan, had wanted to go to war again, while Wrex had the foresight to try and figure out a way to save their race. Wrex had to kill him in self-defense, then decided to abandon his people.
Liara provides a rare heroic example if you bring her with you on Noveria - she helps you kill her own mother, Matriarch Benezia. Benezia was an outright villain. Well, notquite.
In Mass Effect 2, if you can resist Morinth's mind control, you and she can kill her mother.
And also in Mass Effect 2 you can convince Jacob Taylor to abandon his father on a planet with the crew that he had driven mad through forcing them to eat toxic food that caused neural decay. You can even Leave Behind a Pistol for him with only half a thermal clip.
Psycho Mantis of Metal Gear Solid woke up one morning to find his entire village in flames, all its inhabitants, including his father, dead, victims of his psychic powers (his mother was a victim of Death by Childbirth). Well, that's how he tells it. He probably just did it for shits and giggles.
As his powers began to develop as a child, he started to hear his father's thoughts. He came to the realization that his father really and truly hated him because he was responsible for his wife's death, though he acted like he loved him. One day, Psycho Mantis burned his entire village to the ground out of pure hatred for humanity, and especially his father.
The trope is also used symbolically, and for the protagonists even, with Snake killing his "father" Big Boss, Raiden killing his "father" Solidus, and Big Boss killing his "mother" The Boss.
That first one, while not lacking for symbolism, isn't symbolic in the way implied with the quotation marks, what with Big Boss actually unambiguously being Snake's biological father. Well, a little ambiguously.
In Star Stealing Prince, Snowe's parents are dead. Edgar and Lina weren't dead from the start like you're led to believe, they faked their own deaths and appear later in the Sepulcher, where they try to destroy Snowe and his friends and Snowe and his friends have to kill them in self defense.
The Wolf's past is shrouded in mystery and what is known of his history is mainly patched together from stories and unreliable rumours alone.
This aside, it is believed that both his parents died from natural causes in close succession shortly after his eighteenth birthday.
The Many, that annelid Body Horror from System Shock 2, certainly want to do this to the "Machine Mother" who created them. Instead, the avatar of SHODAN kills them.
Balxephon in Tactics Ogre killed his father, and later on his mother died as well. He had his brother blamed for it.
The backstory for the Demoman in Team Fortress 2 claims that his fascination with explosives began at age six with an attempt to kill the Loch Ness monster. That first attempt cost him both his original adopted parents. The WAR comic contradicts this by having his mother alive and living with him, leading to a Retcon stating that he blew up his adoptive parents, which led to him reuniting with his birth parents.
Baek Doo San in Tekken killed his father in a training accident. The fact that his mother had abandoned them after his father fell into alcoholism didn't exactly do wonders for Baek's mental stability after the fact. Meanwhile, the Mishima tend to try to achieve this. Constantly. except Jinpachi Mishima who was sealed under the Hon-Maru compound by Heihachi who want to seize the Mishima Zaibatsu.
Arthas Menethil, of Warcraft fame. After losing his soul to the runeblade Frostmourne, he returned to Lordaeron and slaughtered everyone, up to and including dear old dad. In fact, the cinematic trailer for the Wrath of the Lich King expansion lays on the irony by juxtaposing his dad's words of wisdom with the the now-Lich King commanding his vast undead armies.
King Terenas: W-what are you doing?!
Prince Arthas:Succeeding you, father. (stab)
Fortunately, karma came back with a vengeance, as Terenas' soul resurrected the heroes who killed him after Frostmourne was broken.
Archipelago: Captain Snow. Started off with birds and squirrels. Later, killed his parents and apparently the rest of his family, sparing his nephew but forcing him to work for his crew. Went on to become the most feared and hated pirate captain in the world until he died of a brain tumor. And nowhe'sback.
In Drowtalesthe three Sharen sisters send mommy dearest to her room permanently so they can rule Chel'el'Sussoloth in a demonic triumvirate.Their dialog as they do it is especially cold.
To elves and drow, killing one's own mother is viewed as the worst crime one can commit, with someone who does it or willing to do it being viewed as the worst kind of person. Drow insults reflect this, with "Motherkiller" and "Motherkilling" being the most used insult and curse by their race.
In Girl Genius, Anevka Sturmvoraus shoots her father in the back; she never shows the slightest regret, but then, it's his fault that she's a Brain in a Jar controlling a robot body. Or rather, a robot that only thinks she's the real Anevka, but she doesn't know that. The second novelization strongly implies that she killed her mother as well, though it doesn't give any context.
An interesting example in Gunnerkrigg Court, where Annie kills her mother without realizing it by simply being alive, due to them both being fire elementals. However, in chapter 36, her father is confirmed alive.
Jack: Drip was told by his horrific grandmother that he had killed his parents, in some roundabout way about his birth forcing them to live in a bad neighborhood where they got brutally murdered. But then in an arc showing how he became the Anthropomorphic Personification of Lust it's shown that thanks to the odd nature of time in the afterlife he actually did kill his parents, Lucifer led him to believe that they were an ex-girlfriend of his and her husband, and he didn't realize his mistake until he dropped their baby on his mother's torn open ribcage and got a good look at him. And Drip's daughter Lita is more than a bit obsessed with killing him for what he did to her mother and to herself, even committing suicide in order to follow him into hell and kill him again, though she really had no idea what she was getting into.
Jared murdered his own father, the fate of his mother is as of yet unrevealed, though it's likely she met the same fate.
Richard of Looking for Group admits having killed his own father. In fact he's proud of it. Actually, he thinks of it as a funny story. But then again, anything involving killing is funny to Richard.
Dad: Um... Well, you see... erm... I'm building this new machine in the basement and the TV had some really useful part...
Alice: Dad, If you finish that sentence I will be forced to make myself an orphan...
Early in the prequel "Start of Darkness" (to The Order of the Stick), Xykon decides to leave home and turns his parents into zombies on the way out. He had previously done the same to his grandmother.
We don't know if Xykon killed his grandma or she just died of natural causes and he zombified her then, but he definitely did kill his parents by siccing zombies on them and then zombified them.
Mozenrath from Disney's Aladdin did much the same to his mentor/master, who was apparently raising him at the time.
Keith Keiser of TwoKinds killed his drunken father in self-defence after said father had killed his own wife. On top of it, he was accused of both murders and banished.
Turns out the intelligent general murdered her when he found out she was form the other Bastin nation, the one without the compulsion to follow any order.
The Uricarn from The Wotch is a self made Last of His Kind. It's likely he killed his parents, because in an aside, he regrets killing them all while he was still a kid. He wishes he left a female alive.
Black Mage from 8-Bit Theater may be this; we know he's killed his (blind) brother and has said he "wouldn't use the present tense for any member of my family" (with a blood splatter in the background, no less).
"It would have been cruel to let him live after what I did to his eyes."
In Interviewing Trey (the sequel to Interviewing Leather), the supervillain Jack O'Knaves mentions how his parents were killed right in front of him.
In Survival of the Fittest version one, Cillian Crowe and Daphne Rudko both murdered their own parents, though Cillian was confined to an insane asylum due to his actions while Daphne got off scot free.
Worm's Regent aspires to this, but since his father is the Emotion Eater villain Heartbreaker who enslaves women and forces the children he has by them through Training from Hell this is pretty justified.
Fire Lord Ozai from Avatar: The Last Airbender , although he used an assassin (his own wife, Princess Ursa, who he convinced to use a colorless, odorless poison and convinced her since Azulon was going to make Ozai kill their own son Zuko).
The Omnicronians of Futurama eat their mothers when they grow up. Leela understandably regrets telling a baby Omnicronian that she hoped he would always think of her as a foster mom after he tells her this.
Leela nearly does this herself when she and her mutant parents are reunited. She takes the photos they have of her as proof that they are creepy stalkers who murdered her birth parents. Her parents go along with it because they'd rather die than let their daughter live with the shame of being a mutant. Fortunately, Fry and the others arrive just in time to reveal the truth.
In Iron Man: Armored Adventures, Justin Hammer’s father died under mysterious circumstances and Justin comments about a deity that did whatever necessary to gain power. Nick Fury even suspects that Justin killed his father to take control of Hammer International.
In one episode a Jerk Ass classmate implies that Tony did this to his father because of their (actually friendly and good-spirited) competition to one-up each other's inventions. It's completely false and Tony does not take it well at all.
It is very subtly implied in the episode "Easy as One, Two, Three..." of The Legend of Calamity Jane that Conrad killed the mother of him and his two brothers. He spends the episode repeating her advice and what her opinion would be of their actions, but when one of his brothers asks why he cannot just leave her in her grave, he responds that he did leave her in her grave.
Warden: [sombre] When I was a young boy, I saw my father murdered in front of my eyes. [suddenly cheerful] By me.
On South Park,Cartman turns out to be this, after the revelation
In Spider-Man: The Animated Series, the Kingpin is as strongly implied to be this as the censors would allow. After being left for the police by his father in a robbery gone south, he walked out of prison with the physical strength, connections and mentality needed to build his empire. It's not made clear what he did to his father, but Smythe is shocked that even Kingpin could be so ruthless. Near the end of that storyline, the Kingpin makes his own son Richard take the fall for Kingpin's exposed scheme. After his wife leaves him for this betrayal, the Kingpin is left alone holding a photo of his shattered family, bitterly wondering when his own son would take his revenge.
Bison: Yes, yes, I killed your father! What is it with you women anyway?! I killed my father too and you don't hear me whining about it!
Teen Titans: Raven destroys Trigon at the end of the fourth season, and he's never seen again since then.
On December 14, 2012 in Newtown, Connecticut, Adam Lanza had shot and killed his mother Nancy before embarking on a mass shooting at Sandy Hook Elementary School, in which he murdered 20 children and 6 adults before killing himself.
Atif Rafay, who (with the help of his friend Glen Burns) allegedly murdered not only both his parents but also his severely autistic older sister in Bellevue, Washington in 1994. The case is notable in that while the crime was committed on American soil, all the people involved - victims and suspects - were Canadian citizens; the Rafay family had moved to Bellevue from Vancouver, BC not long before the murders and both Rafay and Burns went back there after being released and before coming under official suspicion by Bellevue's police. This resulted in cross-border cooperation between Bellevue police and the RCMP to get confessions and arrests, snags involving the possibility of the death penalty note Canada does not have the death penalty and will not extradite its citizens to face foreign courts if such a verdict is considered and myriad other legal wranglings before finally going on trial in 2004.
Brian Blackwell bludgeoned his parents after he used their expenses to fabricate being a semi-pro tennis player, and they called him to explain. During the murder he was 18 years old, and left their bodies to decompose for a year in what was once their house until the police found them. He is now serving a life sentence, although his case was notable for being the first example of using Narcissistic personality disorder as a defense before a court.
Caril Ann Fugate, the teenage girlfriend of 50's spree killer Charles Starkweather, was allegedly involved in the murders of her mother, stepfather, and sister. Like Lizzie Borden however, it will probably never be known for sure the true extent of her guilt (or innocence) in the case.
Catalina de los Ríos y Lisperguer aka La Quintrala, a legendary female landowner from Colonial Chile, poisoned her father with the help of her mother as revenge for taking her off his testament and leaving all of the family riches to the Catholic Church. That wasn't the only crime she did or was accused of commiting. Her Quintrala nickname, coming from her red hair, is a synonym in Chile for "a really, REALLY evil adult woman".
Gina Grant was a 19-year-old orphan when Harvard admitted her. What she didn't mention on the form was that the reason she was an orphan was that she bludgeoned her alcoholic mother to death with a candlestick when she was 14. She served six months and went back to school (not a full example as her father had died of cancer a few years earlier).
Kip Kinkel killed his parents after he brought a gun to school and he was worried what they might do to him and after years of in his eyes failing to live up their expectations and apparently loving his older sister more, he then went on a shooting spree at his school killing two students and while he was reloading some students managed to gang up on him and disarm him, he was sentenced to life in prison without parole.
Lizzie Borden (allegedly) in 1892. She was acquitted, and there are a variety of books offering various theories of the case, with a range of possible suspects, including Lizzie's older sister Emma (who if guilty, would qualify as well). As Andrew Borden had been a pretty despicable and hated character who had swindled a lot of people in his business career, the range of suspects should have been pretty large after all.
"Lizzie Borden took an axe and gave her mother forty whacks, and when she saw what she had done she gave her father forty-one"
There's the Menendez brothers who killed both their parents with shotguns to gain their considerable wealth in August 1989.
The Roman Emperor Nero had his mother killed. She in turn had probably poisoned her husband Claudius after convincing him to adopt Nero, hoping she could rule Rome through him. When his assassins met her she bared her chest and told them to stab her where Nero came from. Another piece of evidence linking him to Anti-Christ (see above in Mythology).
A rather infamous one in Amityville, Long Island, New York. Ronnie DeFeo shot and killed his parents and four siblings in bed November 13, 1974 at 3:15 am. The hauntings the book and movies based off of the book implies aren't real, though, just the crime.
Full and literal exemple: in Bellevue, Idaho, Sarah Marie Johnson, then 16, killed her both parents the September 2, 2003 because they forbade her to date a 19-years-old boy.
A classic lawyer joke has a lawyer defending a man who is on trial for murdering his parents. During the trial, it becomes obvious that the defendant is indeed guilty, with no mitigating circumstances to speak of. In his closing statement, the lawyer asks the jury to have mercy on his client, who is, after all, an orphan.
That's actually the working definition of "Chutzpah" (see the Tabletop RPG section above).
Yet another joke is about a little dragon who's crying. When asked where his mom and dad are, he says he ate them. When asked if he knows what it makes him, he says "Yes (sobs). A complete orphan".
One case in Medicine Hat, Canada. A young girl, influenced by her much older boyfriend, murdered her entire family.
In Finland, a teenaged girl coaxed some older boys to kill her mother over domestic differences; fortunately, the crossbow bolt intended to do the job only grazed her skull, and she managed to escape.
In 1954, an incident happened in Christchurch, New Zealand where Pauline Parker and her friend Juliet Hulme killed her mother. Their story was made into film by Peter Jackson, Kate Winslet starred as one of the girls.
One that changed (a small part of) history: One fine summer evening in Nepal, the Crown Prince, Dipendra walked into a family dinner and shot the whole place up, killing his father, King Birendra, his mother, Queen Aishwarya, two of his siblings, and five other relatives, before killing himself (although he would then take a few days to die). As a result, his uncle Gyanendra took the throne. Through a long series of events, this massacre leads to the abolition of the Nepalese monarchy in 2008.
That's the official version, anyway. Many in Nepal accused Gyanendra of arranging the massacre (in collaboration with Chinese spies) and framing Dipendra, so that he could have the throne for himself. Fueling this theory is the claim that the right-handed Dipendra was "shot himself" in the left side of his head, which is a relatively unlikely suicide.