The CyclopsSerial Killer fits this trope to a T: he was born with a brain defect that made him unable to secrete oxytocin, causing him to be unable to feel pleasure except when killing. First he started murdering small animals, then committed his very first murder as a preteen. After killing several women and a convoluted series of events he ends up switching to a bodywithout this brain defect, and he hates it.
Dr. Angus Bumby from Alice: Madness Returns is a textbook example. He presents himself as dedicated to helping his patients get over their trauma. In reality, he brainwashes his patients and sells them into sexual slavery, completely indifferent to the harm done to the children and their families as long as he makes money from it. He also raped and murdered Alice's sister Lizzie when she refused his romantic advances.
Justine from the Amnesia: The Dark Descent expansion pack of the same name is strongly implied to be one, with a healthy dose of Narcissistic Personality Disorder on top of it. She captures her three suitors, tortures and mutilates them to roam her dungeon along with several other hapless bystanders who get roped into a sick "game" of hers where she forces a young woman actually Justine herself after taking a Laser-Guided Amnesia potion into Sadistic Choices about whether or not to save them or be killed herself. Also of note is that Justine's father was a psychiatrist and clearly knew something was wrong with her (and the game is set prior to sociopathy being fully defined) before she killed him.
Assassin's Creed Syndicate gives us Maxwell Roth. He first appears charming enough to get Jacob Frye onto his side with reasoning that he doesn't like Crawford Starrick giving him orders. Then he shows his true colors in a mission where he attempts to burn a factory full of child workers inside. When Jacob Frye saves the children, Roth decides to burn down a theatre full of innocent people. It has even been stated before that when Roth is angry, that means a lot of people will suffer. Worst of all, when he is finally killed he still feels satisfied, for all the evil that he has committed.
Irenicus and Bodhi from Baldur's Gate II: Shadows of Amn. In their case, it's a magically caused condition, though from what we hear, they weren't exactly nice people before.
There are several party members that qualify as well. Kagain is a fairly high-functioning example, able to function in society and forge relationships, but unclear on the whole morality thing and preferring the simplicity of "violence for gold". Montaron is medium-functioning, he lives for violence and cares nothing for life, including his own, but has enough self-control to not go on murder sprees or mess with the big fish in the pond of organized crime. At the low-functioning end, there's Tiax, who is severely delusional and only maintains the barest minimum of self-control necessary to use magic, and Korgan, who is a Deconstructed Character Archetype of the typical D&D murderhobo, showing exactly what kind of person is drawn to the lifestyle of killing things for money they immediately spend on booze.
As goofy as she is, Gruntilda from the Banjo-Kazooie series definitely fits the bill. She's introduced trying to steal a little girl's beauty due to a perceived slight towards her massive ego, and she only gets worse from there. She practically revels in being as awful as possible, as shown by her enslaving the friendly Clanker and turning him into a living trash compactor, or beating her loyal henchman Klungo to a pulp for his failures. Even her own sisters don't mean squat to her, since she'll kill them for losing a game show even though they saved her life.
Bendy and the Ink Machine: As more of Joey is revealed throughout the game, he begins to exhibit all the traits of a classic sociopath. He has absolutely no empathy for his employees, keeping them in horrible work conditions and replacing them on a whim. He has incredible ambition and ego, often taking credit other people's work while contributing nothing of his own. And he manipulates others with his talk of dreams and belief when in reality, he doesn't even believe his own rhetoric and is merely putting on a facade.
Relius Clover, an unabashed Archnemesis Dad and Abusive Parent extraordinaire who, after gaining the ability to see a person's inner soul, views other human beings as tools to be manipulated or guinea pigs to be experimented on because he quite literally can't see them as meaning anything more than simple inanimate objects. And in what can only be considered a seriously messed up logical extreme of the page quote, he even turned both his daughter and his wife into puppets. Completely unapologetically. For Science! And then he attempted to kill his son when he demanded an explanation.
Hazama/Yuuki Terumi, whose sociopathy stands in stark contrast to Relius, is an arrogant and extremely sadistic spirit who greatly relishes the physical and psychological suffering he inflicts on others and feels absolutely no remorse for anyone he hurts. He was directly responsible for the creation of the Black Beast, a monster that ravaged the world 100 years ago. He was then Brainwashed and forced to join the Six Heroes to help stop it only to betray the group and kill two of its members. The only difference between his identities is how he portrays it: As Hazama, he does it all with a thin veil of fake politeness. As Terumi, he doesn't even try to hide his utter contempt for everyone and everything.
Hades Izanami is a classic Sociopath. She is charismatic, manipulative, and wickedly intelligent, even through her batshit insanity, but is simultaneously utterly bloodthirsty and utterly devoid of anything remotely resembling empathy.
The only thing that matters to the Wasp King is power, and he'll sink to just about any low to get it. He brutalizes any bug unlucky enough to be in his way, is implied to have tortured the former wasp queen with his fire magic, forces his subjects to live in squalor, and is more than happy to sacrifice his men if it conveniences him, the very same men he brainwashed into being suicidally loyal to him. Further ticking off the sociopath checklist is his disintrest in anyone other than himself, his violent temper that flares up when faced with the slightest inconvenience, and a horrible upbringing that set him on the path he walks today.
Mothiva is nowhere near as evil as the Wasp King, but still fits the bill as a non-criminal sociopath. She has charmed hundreds, if not thousands of bugs with her seemingly saccharine-sweet, bubbly personality, but it's a facade concealing her true nature as a rude, clout chasing egomaniac. She's only an explorer for the sake of fame and attacks Team Snakemouth when they threaten to overshadow her. Later, she pulls a reckless publicity stunt that would've jeopardized Team Snakemouth's attempts at forming an alliance with the Termite Kingdom, and couldn't care less about the fact that she could potentially doom Bugaria in the process. The only person she sees any value in is her teammate Zasp, but only because he's useful to her. If he's the first to fall in their boss fights she isn't concerned with his well-being, just annoyed with his perceived weakness before reviving him.
The roachscientist duo from Upper Snakemouth were willing to replicate the immortality-giving powers of the Everlasting Sapling at any cost, no matter who must suffer for that. They kidnapped countless bugs and forcibly used them as test subjects for the cordyceps fungus in order to find the way to make them immortal, only for their experiments to fail and turn them into violent undead monsters, a fact that does not concern them in the slightest. They also callously throw away any failed experiment, one of which ended up becoming Leif, and when one of their colleagues suggested that they need to stop, they shrug off their concerns as preposterous, claiming that they are so close to creating something greater than gods. This ultimately ended up becoming their undoing, as their supposed ultimate guardian broke free and killed them all, yet the monsters they created forever serve as the reminder for all the cruelty they performed for the sake of finding immortality.
A friendly nerdy character in Bully flat out calls Gary, your supposed "ally" in the game, a sociopath (the main character doesn't know what that means). It turns out the nerd was right, and all it took was for Gary to run out of medication to become a sadistic sociopathic lunatic who takes control of the entire school, ties up the headmaster, and then attempts to take over the entire town.
Wicked of The Caligula Effect has a rather fitting name. She has very low trust in other people, and the biggest thing she derives pleasure from is watching other people's relationships fall apart, be they friendships or romantic relationships. This is why she acts friendly towards Naruko before kidnapping her and trying to get the Go-Home Club to think that Naruko is the real Wicked. Also, it's an indirect cause of her hospitalization — she attempted to push a girl off a bridge after convincing her that her boyfriend hated her, but she trips and falls off the bridge.
The Doctor from Cave Story. All he cares about is having absolute power over everything and everyone — the lives he violates and ruins along the way don't concern him. He was manipulative even before he got his hands on the Demon Crown, as he joined the research team and served as their medic specifically so that he could, well, get his hands on the Demon Crown.
Child of Light: Norah/Nox fits the criteria for a sociopath following her mid-game reveal as Evil All Along. She feigns a friendly, caring persona towards her stepsister Aurora prior to the events of the game, and when she re-encounters her in Lemuria, continues her façade to gain the trust of her friends as well, aside from some Fantastic Racism conflict with Robert of the Bolmus Populi. She guides Aurora to the magic mirror in the sky that would take her home to her dying father, but it was rigged to transport her to a prison tower instead, where Aurora is confronted with her stepmother, who reveals herself as the Queen of the Night. Nox then drops her act and gleefully tells Aurora that "Norah" was a fake persona the entire time and all part of a plot to kill her. Fortunately, Aurora's crown has a protection spell that makes the Dark Queen's killing spell merely knock her unconscious, but the poor girl is left devastated by the betrayal. Nox then proceeds to imprison all of Aurora's friends in the tower in a separate room with the intent of leaving them to starve to death, and is heavily implied to be involved in the ogre attack on the Piscean village that leaves Genovefa as the Last of Her Kind. It feels extremely cathartic to give the bitch a solid beating in the penultimate boss fight, as she could debatably be the most evil character in the game, even more so than the Queen of Night herself.
Byakuya Togami shows a lot of traits with how flippantly he treats the school Killing Game. He crucified Chihiro's body to make the "game" more interesting. During the investigation, he calls Chihiro's body just an object, and after Mondo's execution, he claims it was a disappointing ending to their game. Also in the investigation, he doesn't care that they left Toko passed out and claims they'd be better off if she was dead. In the daily life of Chapter 4, he tells Hina that he hopes Sakura would die after she's exposed as Monokuma's spy. He displays a typical smug self-importance and never acknowledges the ideals of others — believing only he is right. And the only reason he joins up with the others in the end is that he finds exposing the mastermind to be more interesting than participating in the Killing Game if no one will participate. However, his appearances in later media make it clear he doesn't have the condition; among other things, he puts his life on the line along with Makoto and Kyoko to rescue Class 77 from Alter Ego Junko.
Celestia Ludenberg downplays this somewhat. Although she fulfills most of the criteria for sociopathy, such as Lack of Empathy, her nonstop lying, and doing anything to get what she wants, she'll lash out if someone asks too many questions about her name or past. Plus, a complete sociopath would come off as genuinely friendly, charming, and warm, whereas her attempts at acting as such come off as cold, and from the beginning, it's implied that she never had many friends. When you get down to it, you might even be able to say that Celestia Ludenburg (the persona) is a sociopath, but Taeko Yasuhiro (the actual person) is not. Despite this, it didn't stop her from masterminding two deaths and claiming not to feel guilty about it when she is set to be executed.
Junko Enoshima, the Big Bad of the Hope's Peak saga, is a unique case, overlapping with an unspecified mental disorder as whatever condition they have, it's not an exact match for anything clinically documented.
For points they hit: Need for stimulation and hatred of boredom (because of her Ultimate Analyst talent, everything was boring to her- except despair, which is too illogical to properly analyze), impulsiveness (she kills her own sister on a whim), Lack of Empathy (her only reaction to others suffering is to be delighted), superficial charm (she's a famous fashion model, it comes with the territory), hedonism (she spreads despair to make the world interessting for her), and grandinose sense of self-importance (she sets herself up as the goddess of Ultimate Despair.
However, they have some traits that contradict a diagnosis of clinical sociopathy. Word of God is that Junko genuinely cares about her loved ones, such as Matsuda, Mukuro, and her classmates and feels horrible when they come to harm at her hands; she's just so sadomasochistic that she enjoys this emotional pain, and her love does not take precedence over her despair fetish. Zero shows (in the form of her amnesiac self, Ryoko Otanoshi) that if she didn't have her despair fetish, she could form genuine relationships and protect the people she loves.
Dante's Inferno: Lucifer invented evil by rebelling against God, and has decided to spend his eternal imprisonment trapping any soul he can in eternal torture. He uses his shadow to corrupt people on Earth, sadistically taunting anybody who opposes him. The ending reveals that he has learned nothing from his imprisonment, and simply wants the entire universe gripped in his wretched claws.
Devil May Cry 3: Dante's Awakening: Arkham, big-time. Everything he does throughout the game is because he wants Sparda's power just for the sake of having it. He speaks of the concept of "Evil" with religious fervor and delights in the fact that he used both Sons of Sparda and Lady for his nefarious ends. He talks about his wife's murder at his hands like it was a simple requirement, has no qualms with hurting his own daughter to get what he wants and embraces the mass genocide of humanity like it's the Rapture all because he wants to have the power of Sparda, who he says sacrificed a woman "to become a legend", completely missing the point that Sparda did it to save humanity and that the priestess was willing to do the sacrifice if it meant sealing away the demons. Even in his final moments, he furiously questions Lady what he did wrong like she's simply bothering him, and even having the gall to ask her if it was "really so awful" and to help him, uncaring for how much of her life he ruined with his actions. While other villains in the series simply dismiss human emotion and morality as things that make humanity weak, Arkham is just plain incapable of understanding them and makes no effort to try.
President Zazz admits that due to his immortality, he has no empathy for Zeta's citizens and that their suffering means nothing to him. However, he can maintain at least some degree of good publicity with his charisma, though he hates doing it because he sees non-humans as far too beneath him to warrant such effort. Despite his cruelty, his ego and pride are so overblown that he believes himself to be the righteous hero of humanity and expects his species to praise him once they're revived. He wasn't always like this, since he showed genuine grief over his fellow humans in the past.
Clyde seems to be a high-functioning sociopath who can hide his sadism and callousness behind a polite facade, but he later displays Hair-Trigger Temper when his pride is wounded and can't help but gloat about Zetacorp's crimes when he's on the job. It becomes clear that he's actually a low-functioning sociopath who normally has so little impulse control that he needs to brainwash himself into keeping up appearances.
While most of the villains in Eternal Sonata are bonafide psychopaths, there are two who stand out the most. Fugue is the sadistic Evil Genius of the group who's Establishing Character Moment has him attacking Frederic and Polka just because he's wet. Meanwhile, the teenageCount Waltz, the Big Bad himself, is just as bad, if not worse. He creates a substance called mineral powder which is said to cure diseases but also has a side effect of turning people into monsters. Why does he want to do this? So he can have an army to help rule the world as he feels that this is the best way for people to remember him.
The Evil Within: Ruvik definitely qualifies. He showed sociopathic tendencies at first by dissecting animals, and when Laura was assumed to have died, moving on to people. His response to Dr. Jimenez's horror towards the victims of his traps seals the deal on this one:
Ruvik: These vermin? These microbes? They're mine to deal with as I please.
Stefano: Fear...radiates from you. It’s beautiful, but not yet finished. I am Stefano and now, you are my art!
Stanislaus Braun of Fallout 3. A heartless Mad Scientist who previously engineered the worst atrocities of the vaults, he's currently living it up in a virtual reality scenario in which he can torture the other real inhabitants to his heart's content. Braun's character is a checklist of all the most notable traits of psychopathy: he's a narcissist, holding his intellect in very high regard and expecting the player to follow his commands without question. He's glibly charming, feigning friendliness in his guise as Betty, and even expresses admiration if you play along with his games — but will turn on you in a heartbeat if you disobey him. He wants to be entertained on a near-constant basis, ultimately deleting scenarios once he's exhausted their potential for fun, and enlists you to amuse him through a progressively more sadistic array of crimes across Tranquility Lane. He lies and manipulates without so much as a guilty twinge, roping thousands of innocent people into the vaults with the promise of surviving nuclear war, offering his own vault residents the hope of enjoying a virtual heaven in the Tranquility Loungers, and manipulates you into cooperating by withholding the location of your father. Finally, he demonstrates a total lack of empathy for anyone he tortures and kills over the course of his games, and takes great delight in observing the suffering of real people — whether it's making a little boy cry, breaking up a happy couple's marriage, or murdering everyone on Tranquility Lane only to bring them back and torture them again. And if you ever manage to Mercy Kill his captives, his biggest complaint is that you took away his toys.
A subtle version of this occurs in the Fallout: New Vegas DLC Lonesome Road. Should the player progress through the area with a positive reputation with any of the three dominant factions in the Mojave, Ulysses will accuse them of being an unthinking pawn of a larger, flawed organization. If the Courier has a poor reputation with all three factions Ulysses will accuse them of being a selfish, shortsighted malcontent who blunders into circumstances with far-reaching implications without the slightest concern for how their actions affect others.
Bambi"Buck"Hughes. He was a former Australian soldier before his obsession with brutality led to him getting discharged, and now works as a mercenary. Initially, he behaves friendly towards Jason, but in an insincere way that riles Mr. Brody. Additionally, he is a Manipulative Bastard, holding Jason's friend Keith captive in order to force Jason to go on a Fetch Quest for him to obtain a rare Chinese knife. When Jason talks back to him or fails to find the knife, he decides to punish Keith instead just to re-assert himself over Jason. He is a Lazy Bum, content to lie down in the sunlight, or just hang out at the bar drinking beer, and casually makes jokes about the way he traumatized Keith after buying the young slave. And he's a Serial Rapist who's keeping Keith as a Sex Slave, and after Jason delivers him his knife, he openly admits that he never planned on giving Jason his friend back in the first place, because I Have You Now, My Pretty. Most prominently, Buck displays a defining trait of a Sociopath, being a Smug Snake. Despite all the people Jason has killed throughout his stay on the Rook Islands, Buck still feels confident that he can take care of him by going into the sex dungeon by himself, armed only with a knife. He can't. At all.
Hoyt Volker, the Big Bad. The Don of a massive trafficking ring that sells drugs and slaves centered on the Rook Islands, Hoyt is a man who appears friendly on the surface, but undermines casual small talk with his workers by committing some atrocity or other, like burning one of his men alive for disloyalty. He has a Lack of Empathy for his slaves, dismissing them as his "product", and cheerfully blows up a boat with passengers on it just because the customer doesn't want to negotiate with him outside country lines, heedless of the fact that he could end up killing his own men with pieces of the exploding boat. He orders "Foster"(actually Jason Brody) to go downstairs and torture a prisoner for him (Jason's own brother Riley), and Jason has to go through with it to maintain his cover. And then he learns that Hoyt knew who he was all along, so he tortured Riley for nothing other than Hoyt's sick amusement. Hoyt's only interests in life are making money — and all company profits go to him instead of his men — smoking cigars, enjoying opera music, and murdering people. He also is a shockingly Ax-Crazy man, enough that Vaas, who's very much not a shining depiction of sanity himself, is intimidated into compliance by his boss' anger. Above all else, Hoyt is a Smug Snake — even after Jason, the One-Man Army, destroys half his organization, he still feels confident that he can kill Jason in a Knife Fightupon beating him in a poker game and cutting off one of his fingers. Like the aforementioned Buck, it doesn't end well for Mr. Volker. Really, Hoyt's character can all be summed up in this exchange between Jason and himself:
Possibly Kotomine Kirei. He describes himself as never feeling happiness from the happiness of others, only finding joy in their pain and suffering, and being incapable of loving someone else. Interestingly, because he was born to a very religious man, he considers himself a "defective person" and spent most of his life trying to "fix" himself, only to give up ten years before the story. His ultimate goal is to try to understand why a good and loving God would create a seemingly inherently evil person such as himself. He is definitely cunning and manipulative, an excellent liar when he wants to be (he prefers to amuse himself with Brutal Honesty), and is charming in his own way, although the story's protagonist takes an instant dislike to him. Said protagonist later realizes that he actually does like Kotomine and that the reason he immediately felt a twinge of distaste was because he realized that he subconsciously saw a BIT too much of himself in Kotomine.
Gilgamesh. He has the limited emotional affect, Lack of Empathy, need for stimulation, consummate lying and manipulation abilities, lack of shame or fear, and an inflated ego.
Kefka Palazzo from Final Fantasy VI has no understanding of morality, no impulse control, manipulates the emotions of others, is a rampant liar, and resorts to ever greater extremes to slake his thirst for destruction. Kefka ticks all the boxes. All of this is before he becomes a god.
President Shinra from Final Fantasy VII Remake has no qualms with dropping the Sector 7 plate, killing thousands of people who live on or under the plate, for an excuse to start a war with Wutai, and plans on abandoning Midgar to build a new city in the Promised Land. When Barret confronts him and demands to know what principles he has, President Shinra coldly declares that he will use anyone and anything at his disposal to get what he wants and discard those who are no longer useful to him, and that "There is no room for sentiment or guilt."
Fire Emblem Engage: Lord Sombron is an incredibly cruel tyrant who will stop at absolutely nothing in order to get what he wants. He despises bonds and sees others as a sign of weakness. He frequently kills people when they have served their purpose and views his children as mere tools for him to abuse. Sombron has almost destroyed entire dimensions, not caring about the losses in countless innocent lives. If that wasn't bad enough, once Sombron kills, he revives them as zombies, forcing them bend to his will and be his slaves.
Five Nights at Freddy's: The Purple Man, otherwise known as William Afton, is a sadistic Serial Killer who had killed at least eleven children whose souls would go on to possess the animatronics. Mr. Afton ticks off all the boxes: Lack of Empathy; he doesn't care who he kills, and even his friends and family are at most pawns to be used (with the possible exception of his daughter Elizabeth). Lying manipulator; his intro speech in Sister Location is really well composed, but also doesn't address the question asked of him at all. Constant need for stimulation; the only reason that seems to be given why he kills children is that he likes it and he's able to. Brilliant but also lacking foresight; while he is behind the creation of the Funtime animatronics and has in-depth knowledge on the springlock suits, he displays a severe lack of forward-thinking: he decides to climb inside the springlock suit even when the condition it's in makes it highly likely to kill him, and knows that the pizzeria in the sixth game isn't what it seems but can't resist the opportunity to kill more kids. Both of these examples lead to his death. He seems to be of the low-functioning type since he has a single-minded obsession with killing people, even after being turned into Springtrap.
Forever Home: Barclyss puts up a convincing Mask of Sanity, but it's clear that he has no empathy for any of his victims or his own subordinates, only caring about his own self-pity about the lack of meaning in his life. While he claims to not enjoy his role as an Omnicidal Maniac, he earlier showed sadistic pleasure in watching Xero struggle to save Enda in the Aquadome, showing that others' suffering is one of the few things to elicit a happy reaction from him. Once he loses Fort Cataclysm, he has a psychotic breakdown, showing a lack of impulse control and a need to be in control of the situation.
The Antagonist from Hatred is given little backstory, but states that his "whole life is nothing but cold, bitter hatred" immediately prior to loading up several automatic weapons and going on a massive killing spree, showing little emotion as he does so.
Heavenly Sword: Flying Fox, a gleeful sadist who spends his entire screen time brutally murdering people for his own amusement and uses a woman's corpse to lure out her child. In the animated film, he even plots to kill Bohan and overthrow him.
It's also very common for 47's targets to be sociopaths who got hits taken out on them by one of the many people they backstabbed and/or victimized. Bradley Paine, Claus Hugo Strandburg, Rico Delgado, and Dawood Rangan are all referred to as sociopaths in their descriptions.
Hunter x Hunter: Altar of Dragon Vein: Zegin Highline is a former Hunter examiner who slaughtered all forty Hunter applicants during the 282 Hunter Exam leading to his license getting revoked by the hunter association and ordering his arrest. When he returns he searches for a powerful item called the Dragon Vein in order to achieve “True Freedom” meaning he can steal and kill anyone he wants and have the power to avoid any consequences of his actions. When attacking the Hunter Association airship he nearly kills Menchi and blackmails Netero into giving him the ring that will help him find the Dragon Vein or else he would destroy the airship they are on killing everyone inside and only showing concern that he would have to go though all the ruble to find it. When one of his minions seeks revenge against him for killing his father who was one of the applicants during the 282 Exam all he gives him is an empty apology towards his tragic backstory.
Injustice: Gods Among Us: The Joker in the game proper is more of a Nominal Hero and doesn't get much screen time, but his Injustice counterpart takes this up to eleven by being the root cause for all of the misery that happens in the game. Five years prior to the game, he planted the trigger for a nuclear bomb placed in the heart of Metropolis in a pregnant Lois Lane designed to go off the instant her heart stops beating. He also drugged Superman with Kryptonite-laced fear toxin, causing him to see Lois as Doomsday and kill her by dragging her into space so that the deaths of Lois, his unborn child, and all of Metropolis were on his hands. And the reason why he did it? He was tired of constantly losing to Batman and wanted someone whom he could mentally break all For the Evulz. While the Joker is Killed Off for Real, his actions drove Superman to adopt a hardline stance on crime. That Joker got the last laugh shows he was fully aware of this fact. Likewise, nobody has forgotten about his twisted legacy in the sequel.
Hades from Kid Icarus: Uprising. He instigates a pointless, international war that results in the deaths of millions of humans for no other reason than to harvest their souls to either create more underworld monsters and do whatever else he wants with them (As well as for his own sick amusement), and has absolutely no remorse for his actions. Even when he helps out during the Aurum Arc, it's not out of altruism, it's only because he wants to be the one to destroy humanity. and he still throws Underworld Monsters in Pit's path to hinder his progress just to screw with him.
Vanitas seems to fit the mold at first, but the origins of the Unversed prove he is a subversion. Rather than being callous and lacking in anything but the most shallow emotions, Vanitas is comprised of nothing but negative emotions. And he creates a new Unversed with every negative emotion he has. A true sociopath would not be able to feel deeply enough to create them in the first place.
Nobodies are by their very nature sociopaths since they lack the hearts required to form bonds or experience true emotions. The members of Organization XIII function at varying levels, with the exceptions of Roxas and Xion, the former of which is born under very special circumstances and the latter of which isn't even a Nobody. Another member, Axel, does gain emotional care for Roxas and Xion after hanging out with them, but it's only for them; he is still a sociopath in regards to anyone else.
And then Dream Drop Distance reveals that all the Nobodies had the potential to grow new hearts and feel emotions all along. Xemnas is the one who lied to them and made them believe they were sociopaths all in order to manipulate them and gain control of their minds, hearts, and bodies. And though he acts the most emotionless of them all, he likely had Terra's heart all along, meaning he was just naturally an uncaring monster.
Played absolutely straight with Master Xehanort, the Big Bad of the series and a human to boot, who fits all of the criteria.
Necrodeus, the leader of the Skull Gang whose name literally means "Death God" and who hates light with a burrning passion. When he arrives in Kirby's world, the first thing he does is splitting Kirby in ten weaker fractions, then killing all of them save for one that escaped out of pure luck. Throughout the Kirbies' journey to make themselves one again, Necrodeus consistently destroys them until one is left. And when the Kirbies find a way to make themselves one, that method being Necrodeus's staff, he eats it. A viler villain than everyone up to that point, Necrodeus exists only to make people suffer, and you'll enjoy when the Kirbies kill him to get his staff.
Fecto Forgo manipulates Leon, the leader of the Beast Pack, with honeyed words and promises of a "promised land" the world's previous inhabitants apparently set off to into reuniting him with his other half, Elfilin. To that extent, Forgo had the Beast Pack kidnap hundreds, if not thousands of Waddle Dees and brainwashes King Dedede. He nearly ends up succeeding, even reforming back into his true form, Fecto Elfilis, only to be trounced by Kirby, who extracted Elfilin out of him. Forgo then pulls a Suicidal Cosmic Temper Tantrum in an attempt to destroy both the New World and Popstar. When that failed, he traps Leon in a land of dreams for his failures. He tries to prevent Kirby from saving Leon by shattering Leon's soul and scattering the pieces, only to be stopped by Morpho Knight. But that didn't stop him; he then pulled a Villain Override over Morpho and transforms into Chaos Elfilis... only to lose again to Kirby. The worst part is that Elfilin is Forgo's conscience, and Forgo's still a sociopath after refusing with Elfilin.
The Legend of Zelda has pulled out its share of notable sociopaths over the years. In order of appearance:
While it's mostly a case of Depending on the Writer, most incarnations of Ganondorf are typically depicted as textbook sociopaths. A power-mad despot feels no remorse for anything and will stop at nothing to obtain the Triforce and rule Hyrule even if it means using murder and manipulation. The only exception to this rule is his Wind Waker incarnation, who was portrayed as a Tragic Villain and a Well-Intentioned Extremist. His The Legend of Zelda: Tears of the Kingdom incarnation really ups those traits, showing glee in murdering Queen Sonia for her Secret Stone, feigns good intentions by having the Gerudo peacefully become part of Hyrule before putting them in his crossfire of his warmongering conquests, loves causing pain for the hell of it, and has a monstrous ego with no remorse for anyone.
The title character of Majora's Mask is a textbook example. It loves all of the pain and destruction it causes, cares nothing about the consequences of its actions, and sees everyone else as nothing more than puppets and playthings to use and throw away.
In The Legend of Zelda: The Minish Cap, Vaati is cruel, self-centered, and willing to do just about anything for a bit more power. As his backstory shows, he has no problem with backstabbing his mentor. And based on how aggressive he acts when he pulls off his impersonation spell, he is unable to understand another person's thoughts so as to convincingly act like them. The only reason his plan worked was that he chose to impersonate King Daltus.
Twilight Princess has Zant. He was a member of the Twili race who went insane when denied the title of king for his ambition to conquer the World of Light. After making a deal with an imprisoned Ganondorf for power, he seized the throne by force, turning Midna into an imp and transforming his own people into Shadow Beasts by sealing away the Sols. He then led a full-fledged invasion of Hyrule, committing more atrocities along the way such as executing Queen Rutela in front of the Zoras for resisting his rule. and forcing Zelda to surrender by threatening her people. When Link and Midna unravel his plans he curses Link to remain in wolf form permanently and fatally wounds Midna by exposing her to light. All done with no remorse whatsoever. The fact that he has the gall to pass himself off as a well intentionedKnight Templar only reinforces his sociopathy.
Skyward Sword has Ghirahim, an arrogant and extremely sadistic Demon Lord who seeks to use Zelda's life force to revive his master Demise and pursues this goal with total disregard for the lives around him. Going through his personality traits is going through a sociopath's checklist: superficial charm, feels no remorse for anything, extremely sadistic and relishes the pain he inflicts on others, and will not hesitate to manipulate others if it serves his ends.
A Link Between Worlds has Yuga. A vain and arrogant sorcerer who at first glance seems to be a mere servant of Hilda, helping her in her quest to use Hyrule's Triforce to restore the kingdom of Lorule. At the end of the game, he reveals his true colors when he reveals that he never cared about Lorule's fate and that he was merely using her to obtain all three pieces of the Triforce and rule Lorule as the god he fancies himself as.
Hyrule Warriors: Age of Calamity has Astor. At first, the Yiga Clan side with him because of his ability to manipulate Malice and see the future. However, he ultimately sees them as nothing more but disposable pawns and fuel for his Blight Ganons. Combine that with his Hinox-sized ego and it's no wonder he gets eaten by Ganon.
Morinth of Mass Effect 2: a coldblooded Serial Killer with the ability to destroy her victim's minds while melding, she will gladly manipulate others for her own gain and amusement, forms relationships with others only so she can kill them, sports a pathological desire for stimulation that she satisfies through drugs and murder, claims to be "the genetic destiny of the asari," and has no empathy for anyone. The mission overview after Samara's loyalty mission even says that her biotic powers would have made her an excellent addition to the squad... if her "sociopathic tendencies were mitigated." Though you can kill Samara and recruit her anyway. According to the codex, all Ardat-Yakshi have the potential for this behavior, though few are actually murderers and most are only kept imprisoned in case their condition goes full-blown Morinth — or for fear that someone outside the asari might learn that Ardat-Yakshi exist, an embarrassing cultural secret.
Quarian Admiral Daro'Xen displays several classic signs of sociopathy as well, especially in regards to the geth, whom she plans to — as a race — mind-wipe and return to their "rightful place" as the quarians' slaves. Tali'Zorah flat-out calls Xen insane when this bit of info comes out, showing that even among the anti-geth quarians Xen's stance is seen as radical. Also, Xen apparently used to perform surgery on childhood toys; Tali's response is predictable. Lastly, she shows an unhealthy interest in Legion (your geth squadmate), once expressing the desire to dissect the poor thing to see what makes it tick (which Paragon Shepard is having none of, by the way).
Dr Henry Lawson definitely counts. He's a Mad Scientist who views everyone as pawns or test subjects for him to use and throw away. He controlled every aspect of his two daughters right down to their DNA and has no problem killing them or using them as Human Shields. He has in fact killed several daughters before Miranda because they weren't "perfect". He also sets up a refugee camp for people fleeing the Reapers, only for them to end up as guinea pigs for his experiments on Reaper tech, by turning them into husks, and killing them when they don't meet his expectations. He claims to be saving humanity, but he's really doing it for his own ego thinking that people in the future would see him as humanity's savior.
The captive on Purgatory known only as Prisoner 403, who finds the screams of others being tortured relaxing!
Master Detective Archives: Rain Code has Yomi Hellsmile, who is quite a blatant example: he doesn't care for anyone but himself, lacks empathy, twists any truth that reveals his true nature for all to see as a means to maintain his own reputation, displays a superficial charm to others (when it's convenient), is quite willing to use people as expendable tools, and his recklessness is taken to such extremes that it's what leads to his own downfall. This is when compared to Makoto, whose villainy is driven by love instead, and unlike Yomi, he at least demonstrates he cares for the lives of actually-innocent people; Yomi has none of those traits. He also switches between high-functioning and low-functioning, being willing to mastermind massacres of other people and target others for murder under the guise of it being an execution, while simultaneously emotionally manipulating those who pose the most loyalty to him so they remain on his side.
Bethany from Melody shows every clinical characteristic, but it’s ultimately subverted when she makes her Heel-Face Turn.
Matthias Nilsson from Mercenaries is explicitly stated not to be one. While he has the flat affect, thrill-seeking behavior, and seeming amorality, his sociopathic traits are a result of his being The Stoic and a firm believer in that You Can't Fight Fate. He has no problems with killing because he believes that those he kills are fated to die, and nothing could be done about that. Similarly, he will not die before his time is up, no matter what he does. He is also perfectly capable of empathy and emotional reciprocity, has no problems with recognizing his failings and is possibly the world's worst liar.
Metroid: Ridley establishes himself as a psychotic space dragon by allowing his crew to massacre the K-2L space colony Samus was born to and later fakes empathy when a 3-year-old Samus offers him friendship to lower her guard. Meeting up with the girl again, he recounts eating human flesh to recover from the encounter mockingly telling her that he may have eaten her mother as well.
Naufragar: Crimson: As a result of super soldier experiments performed on him, Hyo becomes a madman who is willing to sacrifice all his former friends in order to continue living. When Athena calls him out on hurting others for his own benefit, Hyo states that he lost the ability to care about other people's emotions. Despite this, he is good at faking kindness as he impersonates Kyo's personality to manipulate the party. He is also very arrogant and egotistical about his new powers, referring to himself as "the Absolute."
Ahg-za-Haru from Nexus Clash is a god-sized vortex of remorseless selfishness that exists to gratify its immediate desires at the expense of everyone else in the multiverse. It's a distressingly successful contender in the Cosmic Chess Game that drives the series.
OverwatchMoira O’Deorain checks off the list of the traditional definition even more than the rest of Talon. She tends to view most human life as disposable lab rats, even referencing to downed foes as "guinea pigs", and as shown with the creation of Reaper, has the power to inflict terrible fates that she deems scientific miracles. She also has a fairly obvious sadistic streak and is so goal-oriented and emotionally cold she seems blissfully unaware of how unlikeable it makes her. Even her appreciation for Omnic life is more of a passing fascination on understanding how their technology works more than genuine empathy for their plights.
Second, as hinted at above, is the Lantern King, who views others as his playthings to the point that he'll complain like a petulant child if you "ruin" his fun by returning Nyrissa's heart to her or killing her.
The Lantern King: (The crowned living flame slowly turns to you, his glowing mask throbbing in rage. His wrath intertwines with the very essence of the surroundings, making the whole world change.) To drink without quenching thirst. To climb a mountain that has no peak. I staged the performance, and you left it without a finale. You took away Nyrissa, my precious toy, carefully crafted of despair and wrath. I could reduce you to dust, revive you, and turn you to dust once more, here and now. But the universe abhors inelegance. So instead I shall repay you — with your own coin!
Camellia, serial killer, sadist, willing to sacrifice human beings to appease a spirit, with a flat affect and uncaring, cold demeanor despite their superficial charm and classy demeanor. And a possible romantic partner if you're willing to indulge her being a serial killer who butchers people to try to appease the spirits she listens to.
Daerun, an oracle of life, is a careless hedonist who does not care at all about anyone or anything and is jaded on pleasure. He charms most people around him. Perversely, he is one of the best healers in the game. He may be subject to hidden depths.
One of the Co-Dragons, Areelu Vorlesh, is a witch who engaged in terrifying arcane experimentation, tormenting people on the academic whim that she wanted to see if she could stitch two souls together. She eventually did it to herself.
Pedestal: Akari Abe is revealed to be this by the end. She projects an image of herself as a cool, collected girl and a dependable friend to heroine Aoi Ooe, unfazed by nearly everything. She has that cold attitude because she's a cold-hearted sociopath only concerned with amusing herself, and she will shamelessly manipulate others by playing into their weaknesses and outright threaten violence if she needs to. She outright told a friend of hers to kill herself repeatedly because the friend annoyed her (and succeeded in getting rid of her), and is the one who orchestrated the death of Shiori Natsume by manipulating her friends to turn against her and ruin her life, trying to drive her to suicide for fun. Even with the one person she seems to care about, she openly tells them that they serve primarily as amusement and relishes her crossing the Despair Event Horizon from discovering the Awful Truth.
Persona 3: Takaya Sakaki hits every qualification for this trope. He's manipulative and a liar; he has a shallow, self-indulgent personality; murders people for fun and money; and most importantly, he absolutely lacks empathy. He tries to kill Ken after trying to goad him to get his revenge on Shinjiro, saying that Shinjiro's words about how such an act would corrupt the young boy have no meaning. He is then unable to understand why Shinjiro would then sacrifice himself for him, a sentiment that he later repeated when one of his fellow teammates sacrifices herself for her love interest.
Tohru Adachi in Persona 4, who initially hides behind the mask of a Nice Guy, though when revealed shows himself as a sadistic manchild who finds entertainment in ruining the lives of others with a tendency of violently lashing out at women who spurn his advances. They do seem a bit more humane in the spinoffs though.
Persona 5's theme centers around bring these types to justice through Heel–Face Brainwashing via "stealing their hearts," the worst of these being Masayoshi Shido, a member of the National Diet who acts humble and generous towards the public but actually sees himself as the only person worthy of leading Japan, looks down on everyone else including his subordinates, uses and disposes of people like tissue paper, and refuses to accept responsibility for any events that might hold him back from his ultimate goal. One need look no further than both Wild Cards — "Joker" and Goro Akechi — to see how casually this man ruins lives without a shred of remorse; the latter moreso, being Shido's illegitimate son.
In Planescape: Torment, The Nameless One's "Practical Incarnation" was this. Ruthless and completely willing to destroy lives to fulfill his goals, he was responsible for many awful things you learn of through the backstory, including your party's Dysfunction Junction status. Notably this is why he's called Practical rather than Evil like one would usually expect; he did evil things not out of enjoyment of them, but simply because he was convinced they were the most effective and practical ways to get what he wanted. The scary thing is... he was usually right.
Despite being a children's series, Pokémon has a couple notable sociopaths.
Ghetsis from Black and White is as sociopathic as you can get while keeping the E rating. He manipulates anyone and everyone he comes across to follow his anti-Trainer rhetoric, including his own son N, has an ego the size of a Wailord, and blames all his plans going south on everyone and everything around him, including the box Legendaries. He doesn't even believe that the Power of Friendship is a thing, despite hiring a scientist that proves hand-on-heart that it most definitely is.
The real Alex Mercer from [PROTOTYPE]. After all, he "wasn't paid to feel." He was so bad that even The Virus who has taken over his body is a better person than Dr. Alexander J. Mercer ever was.
Micah Bell, the Big Bad of the entire storyline, is a very accurate depiction of a true sociopath/psychopath. He is very good at putting on a facade of confidence, has a heightened sense of self, a need for stimulation (as exemplified when he shoots up an entire town), is a pathological liar, an exceptional manipulator, lacks remorse, guilt or empathy; possesses promiscuous sexual behavior, is a cold-blooded murderer from an early age, is irresponsible, and absolutely lacks realistic goals or objectives, as living day to day harming others for the sake of it without goals in life is a common trait in sociopaths. Unfortunately for him, he's also completely unaware of how far people will go to hunt him down in revenge as shown in the epilogue, which perhaps also speaks towards his Lack of Empathy.
Dutch van der Linde might be one. The Evil All Along interpretation of his character makes him a pretty clear sociopath (if higher-functioning than Micah): he's a Manipulative Bastard and tries to make sure his underlings are blindly loyal and likely dependent on him (i.e. he's Arthur's Parental Substitute and rescued Sadie after another gang destroyed her homestead and killed her husband, leaving her with nowhere to go), is a violent criminal who enjoys causing mayhem for the flimsiest reasons, has had several romantic relationships but is incapable of loving anybody, and has no real goal in life aside from spiting the government for daring to tell him what to do, his anti-civilization rhetoric ultimately being an excuse for why the gang can't leave the criminal life.
RWBY: Arrowfell: Bram Thornmane only cares about being seen as a hero and receiving the glory he believes he deserves, is willing to cause Grimm attacks all across Atlas, lies and manipulates anyone that can be of use to him only to have them betrayed when they served their purpose, and shows no concerns for any of the innocents that are put in danger because of his goals.
RWBY: Grimm Eclipse: Dr. Merlot is the main villain of the video game, he once studied at Beacon under Ozpin, but even then the teachers thought something was very wrong with him. Ozpin in particular saw his studying of Grimm as a futile, if not blasphemous practice, causing Merlot to reject Ozpin and Beacon, and continue his studies on his own. He now no longer cares about his original goal of mutating Grimm for humanity's benefit, and now only seeks to further his research. He shows absolutely no remorse for the millions of people he got slaughtered in Mountain Glenn, and is incredibly sadistic while sending his Grimm and robotic guards to kill Teams RWBY and JNPR.
The Boss in the Saints Row series cares for their lieutenants, but makes it clear that they're all in the gang scene for the perks and power. Has nothing but contempt for Julius's attempt to be a "killer with a conscience," with no loyalty to his supposed crew.
Julius: Don't you get it? The Saints didn't solve a goddamn thing. Drugs were still being pushed, innocent people were still being killed... all we did was turn into Vice Kings that wore purple. The Playa: Jesus Christ, you sound like a pussy! Julius: I sound like someone who's not a sociopath...
That said, as of the third game, The Boss becomes increasingly less sadistic and more heroic, and the fourth game revolves around them fighting to save humanity from Zinyak's empire. They can even save Christmas in a DLC mission. Also, they repeatedly state that they're not a sociopath, they're a "puckish rogue".
Adrian Zorlescu of The Secret World. A cold-hearted Morninglight operative, witness reports confirm that he will happily lie, cheat and manipulate in order to recruit for his cause, or to force innocent victims into doing his dirty work; he has no ability to emotionally reciprocate, and even talks in a flat monotone; he lacks empathy, considering the ordered torture of Alina as a "gift" to one of his sadistic lieutenants; finally, when you actually meet him, he's keeping himself amused by tormenting Rada Nastase — the woman he was ordered to serve as a Cloudcuckoolander's Minder to — sometimes to the point of menacing her with a knife.
Shadowrun: Hong Kong has Racter, a Mad Scientist who was diagnosed as this at age 8. His case is quite mild; he is not (recreationally) violent, has decent impulse control and can generally fake being neurotypical, but there are some things about people he just doesn't "get", leading him to prefer working with machines. In game terms, this is what allows him to have his entire lower-half be robotic — Cybernetics Eat Your Soul simply doesn't apply to him. That said, he also expresses Moral Sociopathy, because he believes that his research into his condition and the aforementioned spoiler could vastly improve humanity's lot.
Chairman Yang of Sid Meier's Alpha Centauri. The GURPS supplement outright calls him one. While he's passionate about the greater welfare of humanity as a whole, he displays a shocking lack of compassion or remorse for the suffering his collectivist policies cause for his people. One key tenet of his faction's ideology is "mind over matter" — any amount of pain and suffering can be borne as long as you're able to convince yourself that you're not really feeling pain.
The Sonic Rush and Sonic Rivals sub-series have Dr. Eggman Nega, who unlike Eggman who initially started out as a family friendly version of this trope, but later went on to gain genuine affection and care for others like Sage in Sonic Frontiers, is a much nastier person than the doctor we all know with a lack of care for anyone or anything with the doctor seeking to turn the entire planet into a playground of destruction as opposed to just ruling over it.
Black Doom from Shadow the Hedgehog is as sociopathic as you'd expect the leader of a genocidal alien race to be, which is to say very. He views the people of Earth as livestock for the Black Arms to exploit, and as far as the Black Arms themselves go, he's perfectly willing to sacrifice them when it suits him. He's especially cruel to Shadow, his "son", who he tries to corrupt by exploiting his love for Maria, and will gladly kill him should he defy him.
Infinite from Sonic Forces is a sadistic psychopath who gets his kicks by terrorizing others, and as revealed in the prequel comic, joined Eggman purely because he wanted to spread death and destruction around the world. Along with his cruelty and Lack of Empathy, he's prone to not thinking things through and making monumentally stupid, self-sabotaging decisions that ultimately set Eggman up for failure, making him a very low functioning example of this trope.
Mac Gargan, a.k.a. Scorpion, is a low-functioning example. Disregarding that he's an Ax-Crazy criminal even before putting on the suit, he is also superficially charming, lacks empathy or a conscience, and (as his relationship with Rhino shows) is incapable of forming emotional attachments.
Hammerhead has no qualms about igniting a gang war or stealing humanitarian aid for his own benefit, and will resort to whatever means necessary to "get respect" or "bring the good ol' days back". Even his head enforcers within the Maggia are called sociopaths by their own therapists.
Screwball is this, as well as a Narcissist. Her pathological need for attention and stimulation leads to her crimes escalating from kidnapping hoaxes to acts of terrorism, and she doesn't give a damn about the people that get caught in the crossfire between her and Spider-Man. While she can be clever when she wants to (as shown by her exploiting legal loopholes to keep herself from being arrested in the main game), her poor impulse control leads to her defeat in the DLC, where Spider-Man easily tracks her down to a party thrown in her honor since her colossal ego ensures that she wouldn't miss it for the world.
The true villain of the game, Otto Octavius, develops into this thanks to his tentacles' neural interface magnifying his darker impulses to terrifying extremes. His hatred for Norman Osborn has completely consumed him, and he's willing to unleash a deadly bioweapon on Manhattan and cause further disasters purely to spit in the man's face. He couldn't care less about all the people that are sick and dying because of his actions, and petulantly whines that that only he knows how it feels to truly suffer.
Arcturus Mengsk. Reviewing his key personality traits is like reading through a sociopath diagnostic checklist: superficial charm, a grandiose sense of self, pathological lying, a penchant for manipulating others to achieve his own ends, an absolutely astonishing lack of empathy or remorse for any of his actions, and an insatiable lust for power and dominance that drives his every move. He unleashed the Zerg on a planet populated by billions of people just to overthrow a few hundred individuals at most and establish himself as the preeminent political figure among the Terrans of the Koprulu sector. He has no qualms whatsoever about sacrificing those closest to him if it suits his purposes.
Alarak also fits the checklist, especially in the novellas; lies through his teeth (if he can't murder his problems directly), has sacrificed millions of subordinates for personal gain, incredibly hypocritical and spiteful, causes chaos For the Evulz, and is too caught up in self-worship to stop his debilitating terrazine addiction. This is explicitly a product of his Religion of EvilKlingon Promotion upbringing; if he wasn't a sociopath, he'd be stuck at the bottom and/or dead before he made Fourth Ascendant.
Seth, the CEO of S.I.N., is an Evilutionary Biologist who views others as nothing but test subjects and will freely manipulate others to get what he wants. He hosted a tournament to lure Ryu and use his Satsui no Hadou to complete his BLECE project. Much like Bison, he is extremely arrogant and seeks to rule the world and prove his superiority over humans.
Luca Blight from Suikoden II, the "MadPrince" of the Highland kingdom. You get a good idea of his personality in his Establishing Character Moment in which he orchestrates a massacre of children training to be soldiers on his side to rally up support to restart a pointless war with a neighboring nation while mocking their deaths and regretting not joining in the massacre. He continues to commit atrocities throughout the game, brutally killing scores of people For the Evulz including his own father, while displaying a level of sadism and Lack of Empathy that disturbs even his underlings. Even during his Final Speech, he not only displays a complete lack of regret for his horrific actions but actually boasts triumphantly of them while reveling in his unredeemably vile nature.
Grubba from Paper Mario: The Thousand-Year Door has tons of charm and charisma oozing out from every pore, but it's as superficial as can be. Under the mask is a selfish, vain old bastard who drains the life out of people so he can stay young and fit forever. He's not only completely unapologetic about it, but he's ridiculously entitled and believes that he has the right to use the Crystal Star operating his life-sucking machine in any way he pleases. The closest thing we get to a genuine display of empathy is the respect he shows Mario, but even then, he likes Mario the fighter, not Mario the person, and when all is said and done he's perfectly willing to have him killed when he thinks he's getting too close to discovering his secret.
Super Paper Mario gives us Dimentio who is for all intents and purposes, Mario's Kefka Palazzo and one of the most disturbing examples of this trope in a Mario game. Hiding his monstrous intentions under the veneer of the ditzy jester, he uses his superficial charm to manipulate everyone in the game in order to obtain the Chaos Heart and remake the multiverse in his own image. And it's implied that he's motivated solely by his insanity. He's also very sadistic, killing Mario and the gang with no remorse and cracking jokes about their deaths. He also views love and similar emotions as weaknesses to be exploited. His last act, however, is what hammers home his sociopathy. When defeated for the final time, he leaves a shadow of his power behind to continue controlling the Chaos Heart to ensure that everyone in existence will die with him. Meaning his last act was one that would ensure the deaths of untold trillions. There's a reason why he's considered one of the darkest villains in the Mario series.
Mario & Luigi: Partners in Time has Princess Shroob, the leader of the Shroob race. Though she has the sympathetic motive of finding a new home for her Dying Race, this motive falls horribly flat as she commits various actions that seem driven by pure sadism. Two notable examples are feeding Princess Peach to Petey Piranha in front of a Shroob audience and shooting down the Koopa Cruiser while laughing. Her Lack of Empathy also seems to extend to her sister as she made virtually no effort to free her from the Cobalt Star and showed no indication that she intended to.
Syndicate (2012): Agent Merit's dossier remarks that all Agents are expected to be psychopaths, but Merit is psychopathic even by Agent standards. Also, the corporate, ethically bankrupt Syndicate society effectively fosters a general attitude that the lives of others are meaningless except to the extent they can be used to benefit yourself.
Colonel Jade Curtiss from Tales of the Abyss is a high-functioning example, and very much aware of it. Formerly a Child ProdigyBlack Mage who tortured monsters for fun, he could have been much worse if a mentor hadn't stepped in to give him some sense of morality. As is, his old mistakes haunt him, and it troubles him somewhat that he doesn't understand what it means to end a life.
Rommy in Tales of the Tempest. She has no regard for morality or empathy and does things (usually manipulating others and killing people) only because they amuse her.
Fluffy Fluffy Bun Bun from Toonstruck puts on an obnoxiously cheery and cutesy image to hide the fact that she's actually a cruel manipulator who wants to take over the world and be treated like a god. She has no remorse for kidnapping King Hugh, ordering her guards to capture Drew and Flux, or blasting Flux with her Cutifier.
Kyrie Ushiromiya in Umineko: When They Cry displays quite a few elements of this. While she appears to be nice and smart, she also always shows a cold, calculating side, keeping either a faint smile or a deadpan expression. There are a few red flags of her sociopathy in Episode 3 and 5 (where it's mentioned that she can sometimes "think in an extremely cold and ruthless manner"), and Episode 7's Tea Party makes a full display of it. Not only does she claim that she doesn't give a crap for her daughter Ange, but she isn't overly shaken by the death of her husband and accomplice either and is in fact rather pleased that he is out of the way. Add to that a brief Hannibal Lecture to Eva, and you have one of the scariest characters of the series.
Flowey the Flower from Undertale is a huge one. He cares about no one but himself, exemplified by his philosophy of "kill or be killed." His monologue in the Genocide run reflects a more sympathetic portrayal of The Sociopath than most. Flowey is legitimately upset at his Lack of Empathy, but years of living without the capacity for love have driven him to his sociopathic nature by the beginning of the game, doing whatever he can to feel it again.
It is also implied that the first fallen child, Chara, may have been a sociopath even before their death and return as a demon in the genocide run. When they accidentally poisoned their adoptive father they just laughed, and they later committed suicide so they could merge with Asriel and destroy humanity.
Wadanohara: The original version of Sal/Syake-san is the traitor and Ambassador of the Sea of Death who admits that For the Evulz is his primary motivation for his atrocities. He is manipulative, having had his twin brother Samekichi framed for his actions; he removes Wadanohara's memories and gleefully threatens to destroy her mind by reinserting them; and masterminds the conflict between two warring kingdoms. While he claims to have loved Wadanohara, he has no qualms with leaving her for dead if she rejects his advances, or alternatively, forces Samekichi to watch him assault her if she relents. The remake, however, does give him a genuine love for his mother that the original lacks.
Watch_Dogs: Jordi Chin is strongly implied to be one. As a contract killer, he shows no remorse in killing his targets and doesn't discriminate against assignments; whatever pays the most he'll take it. He openly tells Aiden that he shouldn't waste his time trying to save his sister, and that he needs to "Seperate the morals from the moolah."
While Danny St. John himself is mostly not explored due to his limited amount of screentime in the game, we do find out that he was a cannibal, he killed Jolene just because she knew his secret, and he even gave Lee tips on how to cook him when he got trapped in the bear trap.
From Season 2, we have one William "Bill" Carver, who is happy to beat a man almost to death, smack around an eleven-year-old girl, and candidly and remorselessly admits to killing Reggie in cold blood if Bonnie asks. More worrisome is that he claims that Clementine isn't so different, although the truthfulness of this statement is up to the player.
In Warcraft III, Arthas is forcibly turned into one by Frostmourne, which steals his soul, and takes away his ability to feel any compassion or remorse. Supplemental material reveals that by the time he reclaimed his soul, he was too far gone to care and killed his good and evil sides so he wouldn't be held back in his Industrialized Evil by empathy OR pride.
Sylvannas Windrunner turns out to be one post-suicide, as the sheer horror of The Maw(i.e. WoW Hell) broke her, driving her to make a deal with its ruler to spread death and despair in exchange for power and survival. The next few years shred whatever humanity she had left as she was discriminated by the living and ultimately rejected by her sisters (again), causing her to embrace her role as the new Lich Queen.
The Witch's House: The titular Witch. Despite killing her mother after finding out that she never loved her, she feels no sense of remorse at all and ends up using her dead mother to get her father's attention, only to kill him as well when he doesn't even notice her. After making a contract with the demon, Ellen only grew worse. Despite being able to feel empathy for animals (and even then that does not stop her from feeding a frog to a giant snake and killing his tadpoles), she possesses none for humans whatsoever. From her countless victims to eventually Viola, Ellen wants to make anyone love her, and if they refuse, regardless of reasons, she'll kill them off and revel in their suffering.
Wolfenstein II: The New Colossus: BJ's father, Rip, is a textbook example. He has a Lack of Empathy- he's very racist and bigoted, and he shows no love even for his own family nor any remorse for crossing the Moral Event Horizon by selling out his own Jewish wife, Zofia, to the Nazis. He is a con artist who scammed people out of their money by selling phony ailments, he tricked Zofia into falling in love with him by making her laugh with a monkey joke, and the only time he wasn't a complete asshole to his son (which showed him giving a BB rifle to confront his nightmares) was only to get him to stop waking him up at night with noise after a good ol' beating didn't work. Constant need for stimulation- he is very easily angered, never happy, yells, and gets physically violent, especially when things don't go his way. Abhorrent selfishness- he only married Zofia for her father's money, and when scolding his son for terrorism he manages to make it about his own reputation. Inflated opinion of his own abilities- he didn't shut down his business when Zofia's father told him to, he blames literally everyone but himself for his own problems, and he insults and tries to kill his own son despite knowing that he is, in his own words, a super-killer terror bomber. It ends the only way anyone could possibly expect; his own death.
Ayano Aishi, a.k.a. Yandere-chan, the Villain Protagonist of Yandere Simulator admits to being one in the second intro: she states that she had never felt any emotion and feigns normalcy in her day-to-day life, but after seeing Senpai, falling in love with him, and seeing him get along with another female classmate, she began to feel emotion for the first time in her life: specifically, jealousy and anger the likes of which cannot be fathomed. This is familial, her mother Ryoba was arguably worse, not even seeing what was wrong with Murdering the Hypotenuse so she could be with her Senpai (the protagonist's father) and convinced an entire nation she was set up by the Journalist that tried to expose her.
Your Turn to Die: The floor master Midori (aka, the real Sou Hiyori) is a bona fide psychopath. He is a manipulative sadist who plays with people's lives like toys without a shred of remorse to be seen. He never thinks twice about his cruelty and performs it with a smile on his face, all for his amusement. He is easily the cruelest of the Floor Masters.
Zero Time Dilemma has Mira, who, despite seeming normal, is in fact entirely unable to understand emotions, something which drove her to becoming a brutal Serial Killer who cuts out people's hearts in an attempt to comprehend their feelings. She also doesn't care at all for her boyfriend Eric and plans to kill him too. In the epilogue files, though, it turned out that Eric convinced her to turn herself in, and she was honestly pondering how she could redeem herself.
