The Authority: Seth is a sadistic (implied) child rapist who calls himself the "Six Billion Dollar Bastard". Tired of the Authority's interference in their affairs and afraid of their influence on the world (particularly after the Doctor ruined two presidential candidates by causing them to make out in public), a coalition of interests decided to develop a living weapon capable of defeating the Authority. To this end, they either acquired or kidnapped Seth, an skinny, ignorant, and unambitious hillbilly with an apparent history of being sexually abused by his uncles, transformed him into a cybernetically-enhanced monstrosity, then set him loose inside the Carrier. Armed with over 1,000 post-human abilities, Seth very quickly neutralized all of the Authority, with the sole exception of the Midnighter and Jenny Quantum, who managed to steal a jet and crash it into the side of the Carrier. Despite this, Seth ripped the Carrier from its orbit and scuttled it in Antarctica. Convinced that Midnighter and Quantum were dead, the coalition allowed Seth to retire to a residence within the White House with a harem of prepubescent girls. The surviving Authority members, meanwhile, were all dumped into degrading new lives while the team was replaced by a new team approved by the seven richest governments on Earth. Unbeknownst to all at the time, Seth's scuttling of the Carrier tore a hole in the Bleed.
Churchill, Paul's "pet psychopath," is a dapper and eloquent gentleman who nevertheless seems to have no feeling towards anyone. When he tracks Bob to an old store Bob used to frequent, he tortures the elderly owner with a straight razor. After carving him to bits, Churchill has the place set on fire, informing the old man he can carry his bedridden wife out to save her after Churchill has left him in no shape to even walk. Churchill later captures Bob's best friend Vinnie and tortures him, only cutting it short with a bullet to the head when he realizes Vinnie will never betray Bob. It is also revealed Churchill is the one who set a deal with Russian mobsters to always provide Paul with immigrant boys.
Penny Saetta, Bob's wife, is revealed in the final issue to match her brother-in-law for evil when she reveals to Bob she participated in and did the filming for Paul's activities. Having only married Bob to be a gangster's wife and a self-described “dangerous bitch,” she happily joined in with Paul on his snuff films. When Bob begs her to tell him she didn't involve their son, Penny comments she absolutely made the attempt (Paul just wasn’t interested) before mocking Bob for his morals.
The Vampire MonarchHaigus is the object of Henry Baltimore's pursuit. When inadvertently awoken from his slumber by Baltimore, Haigus spends time tormenting Baltimore turning his family into vampires and saving Baltimore's beloved wife for last. He leaves his wife for Baltimore to find, which forces him to destroy his family when they rise. Haigus spreads his plague throughout all of Europe, occasionally massacring entire villages and leaving the bodies strewn all over for Baltimore to find. He resumes his worship of the monstrous Red King and begins preparing the way for the Red King to return and obliterate the world of men. Haigus eventually tires from the endless pursuits and opts to die at Baltimore's hands, but takes delight knowing he's taken everything from him, and tries to murder Baltimore's only remaining friends before taunting Baltimore how he will never, ever know peace.
The nameless warlock of “The Cursed Bells” story is a greedy, ambitious man who keeps a large amount of vampiric nuns enslaved to him with the lie he will heal them of vampirism, the warlock uses a dark ritual to resurrect a long-dead witch by feeding her ashes and blood to a pregnant woman so the witch rips its way out of her. The warlock has her curse the bells of the cathedral he uses as a base which will Mind Rape anyone who hears the bells into his slaves with whom he will enslave the world and purge any in the way. The warlock also reveals that he gained his mystic knowledge by entrapping a supernatural beast...by leaving a baby for it to eat and catching it while it bathed after the meal.
Blacksad: Ivo Statoc is the Big Bad of the first volume. A lot of the other villains get either tragic backstories in which they were shaped into evil, but Statoc is the only one who was unambiguously bad and depraved from the start. He made Natalia his mistress, and when he found out she cheated on him, he personally tortured her lover to death, killed Natalia in cold blood, defiled her corpse afterwards according to Word of God, and threw money at it to make it all go away. He outright taunts Blacksad by saying that unlike his foe he isn't limited by such silly things like ethics and moral scruples, and is so successful because of his coldbloodedness. The only thing that really interests him is pure, unadulterated power.
Blueberry: "Prosit" Von Luckner from the Lost Dutchman's Gold Mine arc, a Dirty Coward with a sadistic streak and a propensity to shoot his partners in the back, he has a lot of murders on his conscience, the most notable one being when he put a rattle-snake in the boot of his latest partner and then made him 'dance' so that the venom would spread faster in his system. His latest act of villainy is trapping Blueberry and two other people in a cave with no way out, leaving behind a big taunting message for his victims.
Black Noir, the clone of Homelander, gleefully Eats Babies, commits murder-rapes, and eats hearts with a Slasher Smile. The villainy of the other two contenders for worst monster in the comic, Homelander and Butcher himself, was ultimately Black Noir's fault too. Black Noir drove Homelander insane by gaslighting him with the aforementioned atrocities so he would receive the sanction to kill him, which Noir thought was the only thing that gave his life meaning since he was created to kill Homelander. One of Black Noir's crimes was raping Butcher's wife Becky, which triggered Butcher's vendetta against superhumans.
John Godolkin, a twisted Expy of Professor Charles Xavier, runs his own special, private academy for "special" children. However, unlike Professor X, Godolkin simply kidnaps the children and convinces them they're special, never allowing them to go home again. The children are injected with a formula to give them powers and fill out Godolkin's many teams. However, between the ages of 6 and 9, Godolkin begins molesting the children and has the older children join in. Any who prove too troublesome are simply eliminated. Even in the dark world of The Boys, Godolkin stands out as utterly twisted.
Chew: The Vampire, later known appropriately as The Collector, is a being with the ability to gain the powers of others through eating them. As someone who deeply desires to be the ultimate being, the Collector has hunted down, murdered and cannibalized many people, relishing sadistic mind games he plays with them as well. He isn't averse to a round of torture to get information, either. When he captures the hero Tony Chu's sister "Toni" Chu, he devours an arm and a leg and is furious that he can't gain her powers due to her having loaded up on beets, which blocks his powers. Toni, a psychic who can see the future of what she eats, informs the Collector her brother is going to kill him. Her lack of fear and her taunts make him snap and break her neck, even when he had no reason to kill her at that juncture. Even in such an odd and funny series, the Collector is a monster who treats the murder and cannibalism of so many people as stepping stones in his path to glory and power.
The Book of Thoth: While Thoth-Amon is sometimes portrayed as a Noble Demon or given redeeming qualities, here he's revealed as a selfish, horrible monster. Starting as an ambitious orphan, Thoth murders his friend Amon and takes his name to steal Amon's new place in the Ibis Temple. When Thoth's mentor discovers Thoth has been worshiping the Serpent God Set, Thoth magically lobotomizes him to admit he is the 'real' heretic. Thoth has every member of the royal family in front of his chosen puppet killed to place him on the throne and magically lobotomizes him to use him as a puppet and convert all of Stygia to Set's worship, turning it into a hellhole. Thoth proceeds to have his mentor's son crucified, only rescued by the intervention of allies, and is so far gone that he considers having his friend crucified again after said friend saves his life. Thoth unleashes a plague to consolidate his power, which kills his own sister. when he discovers this, he no longer cares and sets about making new plans, any conscience he once had long gone.
Addy Pratt's father Joseph has been raping his younger daughters for what may have been ''years'' as "Family Values" starts. He has enough leadership and charisma to keep a very large group of survivors together in the months after the emergence of the Crossed, but he does so through turning the settlement into a religious cult with himself as its messiah.
Steve from "Badlands" is shown to have been sadistic, ruthless and sociopathic long before the Crossed outbreak, as demonstrated by her treatment of prisoners at Abu Ghraib and her abandonment of people who trusted her after the outbreak. While she's implied to have a Freudian Excuse and seemingly mellows out during her travels with her companions, she proves herself a monster when she shoots Greg in the kneecap to leave him for the Crossed and willingly infects herself at the end.
Federico the Duke of Vallenberg: To try and take over the Kingdom of Benglait, he first created out of nowhere the terrorist organization Grey Ravens to provoke a civil war. He then married his ticket to the throne, Altea, and faked his death to avoid being identified as the leader of the Grey Ravens. Next, after Benglait became a republic without him being able to take over, he launched a series of terrorist attacks that nearly killed even Altea. After that bit him back in the ass as Diabolik and Ginko dismantled a branch of his organization, he launched other attacks, including a willingly failed one against Altea to justify both his faking his death and then his sudden return as motivated by his love for her and the desire to protect her while still trying to cause that civil war.
Mr Logan, the CEO of a pharmaceutical industry, purchased a Synthetic Plague and its vaccine. His ultimate plan was to release the first into the civilian population in order to wait for the panic and then 'discover' the vaccine, all in the name of money. Logan stands in stark contrast to Diabolik and his more honorable methods of theft. He is willing to kill countless civilians with his manufactured plague, just to line his pockets and achieve fame from it.
Dungeon The Early Years: Professor Victor Chambon not only abandons his mentally deficient son, but is also a Diabolical Mastermind who plans on taking over the city by kidnapping the children of the city's leaders and hypnotizing them into assassinating their parents. He also hypnotizes students and uses their bodies to rape women. Some of this was part of his overall scheme, but plenty of it was done solely to satisfy his own desires.
Elephantmen: Dr. Nikken, the man responsible for the program that created Hip Flask and the other Elephantmen, shows absolutely no remorse for kidnapping and horrifically killing thousands of women or for creating a race of sentient beings whose sole intended purpose was war. In fact, he’s rather proud of his accomplishments.
Willy PeteWas Once a Man and is now a fire elemental. But he still has a man's appetites and satisfies them with rape and killing, which, in his case, are one and the same, thanks to his constantly superheated body.And, as we later learn, through cannibalism. Because all normal food is incinerated on contact with him, he resorts to eating superheroes/villains. The worst part is that he doesn't even need to eat'; he just does it because he likes the taste. Oh, and he still manages to top himself at the end of volume five via instant death of ten supers, followed by throwing as much fire as he could through the portal they came through without even knowing what was on the other end, thereby forcing Emp and Mindfuck into a Sadistic Choice from hell.
Now that he's actually been shown as something other than a vaguely defined "heavy hitter" of a supervillain, Deathmonger. Killing Superheroes in the world of Empowered is bad enough. But then Volume 6 tells us that the only reason he kills them is to see if they're one of the few who come back to life after getting killed. If they do, he enslaves them with his superscience and necrotech to serve him however he wants. Forever. The worst part is, he leaves most of them fully conscious of what has happened, but unable to do anything to help themselves. There's really no other category for someone who decapitates a still presumably conscious hero, turns where his head was into a mobile command center, then forces him to use his indestructible severed skull as a weapon. To top that, though, he did it again to said hero's sister who came to try and rescue him. For extra evil, it's implied that Deathmonger doesn't even need them conscious to control them. If there's enough of them left to be aware, he seems to just prefer them conscious. For such a lighthearted series, Empowered sure manages to get a lot of brutal villains.
Ninjette's father. In the span of 'Jette's lifetime, he has beat her senseless on several occasions under the pretense of training, repeatedly undermined her self esteem and made it so she was unnaturally weary of forming interpersonal relationships. When he betrothed his daughter to a Dirty Old Man of an allied clan, Ninjette tried to lose her virginity (the deal was for a virgin bride) but her clan was too frightened of her father to take her up on the offer. Instead, she slept with her childhood friend who was prince of an allied clan. Her father's reaction was to slaughter his bodyguard, castrate the prince and stuff that in his mouth before ripping his head off, fully knowing there'd be a war. He then proceeded to beat his daughter so she couldn't participate. Or piss without blood. Or eat solid food. To top it off, he's been shown as raping a genin around his daughter's age and is bent on dragging his runaway daughter back to the clan without hands or feet to serve as a broodmare
Grendel: Tujiro, the vampiric Kabuki dancer Arch-Enemy of the second incarnation, puts any of the masked vigilantes and crime lords to shame in the evil department. For all his evil deeds, the first Grendel, Hunter Rose, never harm children physically or psychologically. Tujiro, on the other hand is a serial killer who specializes in young boys. First he drains them of their blood while taking one of their eyes as trophies. The other he eats. Tujiro runs a human slaving operation where people are kidnapped for forced servitude and he has easy access to any child he wants. Escaping justice at the hands of the mother of a victim, Tujiro ends up as the pope in a dystopian future where thousands are worked to death and enslaved to him. Tujiro gruesomely murders those who discover his true nature and uses his position to continue his disturbing feeding habits. His ultimate goal is to create a gun to blot out the sun and establish a reign of vampires where humans are nothing but cattle.
Grimm Fairy Tales is a Darker and Edgier retooling of many classic stories and it shows in some of its villains.
The Jabberwocky is the dark ruler of the mad realm of Wonderland. The Jabberwocky lures in innocents to Wonderland-preferably children-or has its cultists sacrifice them to the dark realm. All there are steadily drained of their sanity and find their human forms twisted until they are insane monsters and slaves to the realm's madness. The Jabberwocky spread its corruption over the once happy realm and its ultimate wish is to break free of Wonderland and spread its darkness to the 'real' world as well.
Cal King of the Robyn Hood story is possibly the most evil human villain in the whole mythos. An utter sociopath who bragged about stabbing a gay boy and getting away with it, Cal led the gang rape of the heroine Robin and then carved out her eye for spite. After nearly being burned to death, Cal returned with dark powers and an even greater drive for evil. He slaughters any of Robin's friends he finds, murdered the child son of King John and demonstrated nothing short of absolute glee in hurting everyone he could.
Pan, the dark ruler of Neverland, took control by ousting its previous ruler Barr. Pan proceed to destroy all the Fairies, except his manipulative lover Belle, and set up a dark tyranny over Neverland. To keep his powers and control, Pan used Belle's powers to abduct young boys from earth and devour them to steal their life force. After this, he resurrected them as undead slaves to his will-his "Lost Boys." Pan held almost total control over Neverland and when the only victim to ever escape him returned, Pan attempted to kill him with nothing short of undisguised relish and fury at anyone who challenged his selfish rule.
The Big Bad is Akakios, AKA Samhain. At first he is a man with Laser-Guided Amnesia and a Dark and Troubled Past who is an ally and later lover of heroine Cassandra Hack. After a series of events, however, it is revealed that Samhain is the original "slasher," Akakios, founder of the evil Black Lamp Society. Regaining his memories and true personality, Akakios is disgusted by his former self's feelings for Cassandra, reasoning he could have taken her any time "whether she wanted it or not." Akakios forges the undead slashers into a fighting force and systematically kidnaps or kills everyone Cassie loved, purging the upper echelons of the Black Lamp Society for being "too nice," despite their own atrocities. Akakios plans to spread the slasher disease, turning innocent humans all over the globe into murderous monsters.
For a slasher example, there's Ashley Guthrie. While admittedly amusing here and there, he's still a childsociopath who, even before he became a member of The Undead, did things like strangle a litter of kittens to death (he was annoyed his cat was spending so much time with them) before caving his baby brother's skull in (he was annoyed he was always playing with his toys). After becoming a slasher, his first acts were to cause his father to commit suicide and drive his mother insane. His very first appearance has him killing a little girl in a dream (similar to Freddy Krueger).
Dr.Andrew Rodin stands out in the franchise by virtue of not even being a Slasher, just a normal human. The admittedly sadistic Rodin is the most vile human member of the Black Lamp society, using his scientific genius to create women for the sole purpose of being sex slaves, which often end up abused. He creates other species for the sole purpose of killing others and brutally slaughters a co-worker when she objects.
Hellboy: In this dark world, Nimue, the Queen of Blood, reigns supreme as the greatest monster. Once a mighty sorceress who betrayed the great Wizard Merlin and imprisoned him to live eternally in his own grave, Nimue was imprisoned for 1,500 years by the witches of Britain. Upon her revival to lead the Wild Hunt, Nimue destroys the other witches of Britain and sets about marshaling an army of the Fae. When one ambassador comes to her to say his king will stand with her, Nimue forces him to murder his king, cut out his heart and forge her a new crown with it. Nimue launches vicious purges to ensure there is no threat to her rule, intending to exterminate humanity to the last man. When defeated and being dragged to hell by the witches she'd murdered, Nimue spitefully tears out Hellboy's heart to ensure she won't face damnation alone.
A History of Violence: "Little" Lou Manzi from the comic version is a ravenously psychotic mob boss and Torture Technician who makes Cold-Blooded Torture his hobby. Since becoming the head of the boss twenty years before the story, Manzi keeps a man as a toy, torturing him in every conceivable way he can think of day in and day out till the man is nothing more than an armless, legless chunk of meat—barely alive and conscious. In present, he tries to get the man's partner back to be his victim as well by threatening his family and his young children.
Irredeemable: The Plutonian, after his Face-Heel Turn, seems to be determined to be the biggest one of these he can be. The essential purpose of the book is to ask the question of "What would happen if Superman suddenly turned evil?" Given how the first thing we see him do is murdering a mother and her baby, and that's not even the first thing he's done to cross the Moral Event Horizon, the answer seems to be "He'd fit in this trope pretty nicely, actually." The aforementioned atrocity obviously being just a beginning, he also partially and painfully lobotomized his former teen sidekick, knowing full well that he is effectively immortal and will have to suffer eternal brain damage. He later allows his former compatriots to choose only ten out of millions of Singaporeans to rescue from a massive tsunami (that he triggers, natch) prior to his absolute destruction of Singapore. which he destroyed because the UN representative of the aforementioned country wasn't entirely honest about why his country wanted to elect him as their absolute monarch. After being captured by the Vespa, he is shown to dream of reversing all the horrible things he did - implication being not because he was punished, but out of regret. Except, subsequently, when given the opportunity to redeem himself i.e accepting the telepathic alien's offer to help him, he mercilessly refuses it. As a first thing he does upon returning to Earth, he carves his initials into the USA, uses the new paradigm as projectiles, arranges a kinky threesome with Cutter and Belle Noir, and promises rivers of blood to his followers. Burrows, the man who made a town commit suicide, chooses to kill himself rather than face the Plutonian's plans for earth, and his former Complete MonsterArch-Enemy Max Damage does a complete Heel-Face Turn after being in one of the towns he destroyed.
In addition, there is the leadership of East Meg One, specifically the Diktatorat (Supreme Judge Bulgarin, and Judge Snekov; not Judge Vlad though.) and War Marshal Kazan, The Dragon to Bulgarin. They cold-bloodedly planned the Apocalypse War for years, knowing full well that it would result in the deaths of hundreds of millions, including tens of millions from their own city, and that was the best case scenario. The only one of the group to show any concern was Judge Vlad, the main architect of the strategic attack against Mega City One, and this was because Judge Snekov revealed that, according to the estimates, they would expect to lose 12 per cent of East Meg One, or 60 million citizens, in the initial exchange. When Vlad proposed that the Diktatorat warn the public so that they would be better prepared, Supreme Judge Bulgarin sneered "The people? What have they got to do with it?" implying that the East Meg leadership only cared about their own power and glory and little for their own people.
The League of Extraordinary Gentlemen: Hawley Griffin, aka the Invisible Man, is a psychopath recruited by England so his powers could be utilized for special missions. Introduced hiding in an all-girls boarding school, Griffin's been taking advantage of his powers to rape the teenagers there. He's already impregnated three girls and is apprehended in the process of raping a fourth. When he joins the league, it's not out of any sense of altruism but because he's been promised a cure for his condition, a pardon for his crimes, and a large sum of money. During his tenure on the team, Griffin displays streaks of cruelty and cowardice in equal measure. At one point he beats an innocent constable to death simply because he wanted the man's clothes, and at the climax of the team's first adventure, Griffin attempts to abandon the league to their deaths when things get too dangerous. With the arrival of the invading Martians, Griffin eagerly approaches them and sells out his entire planet to the invaders just so he can rule alongside them. Griffin gives the Martians information on where the human artillery positions are so they can slaughter their opposition, tries to get his teammates killed by selling out their hideout's location, brutalizes Mina Murray while stealing valuable military information, and advises the Martians to use their Red Weed to destroy the Thames and incapacitate the Nautilus. In a series where even monsters can be heroes, Griffin was never anything but a selfish, megalomaniacal snake who was willing to let his race be butchered and enslaved just so he could rule over what was left.
Miracleman: Kid Miracleman, as re-envisioned by Alan Moore and John Totleben, is both so powerful and so psychotic that his alter ego, the young and innocent Johnny Bates, resists uttering his transformation word. When Johnny finally does so to stop the boys in his group home from raping him, Kid Miracleman tears apart his assailants and momentarily considers sparing the one nurse who'd been kind to him. Then he reconsiders, lest people say he's "going soft", and punches the top half of her head into a fine red mist. And that's just the beginning: he then rampages through London, creating possibly the most visceral Scenery Gorn in history by massacring tens of thousands and desecrating their corpses by draping their flayed skins from clothes lines, creating a chessboard with breasts as pieces, and making a rain of severed hands and feet. During his destructive rampage, he prefers to mutilate the children in his path rather than kill them outright.
Predator: Bad Blood: Bad Blood himself, unlike most Predators, or Yautja, who value honor and the glory of thehunt, is an Ax-CrazySerial Killer hunted by his own people as a psychotic criminal. Crash-landing on earth, the Bad Blood kills, tortures and cannibalizes a crew of other Predators before setting off on a killing spree of unsuspecting humans. The Bad Blood routinely makes his kills as gruesome and painful as possible, seeming to cheerfully acknowledge himself as a "sick, psychopathic bastard." While most Predators are no friend to humanity, the Bad Blood has the distinction of being a monster by both human and Yautja standards.
Rex Mundi: The Duke of Lorraine, at first, seems like a decent guy, if a bit harsh with his dead wife, his daughter hating him and trying to win the affections of heroine Genevieve. He soon reveals himself as a vicious monster who masterminds a murderous secret society for the purpose of seizing power in France and launching a bloody crusade to conquer all he can, expelling or just murdering Muslims, massacring anyone who stands in his way, and launching bloody pogroms of 'unfit' minorities. (Nazi allegories in effect.) Lorraine crosses the Moral Event Horizon from the massacres he orders, then by ruthlessly shooting the pregnant Genevieve when she reveals the child she's carrying is hero Julien Sauniere's.
Severed: The nameless Salesman who often goes by Mr. Fisher and who has been on the road for countless centurieshunting down children in order to devour them and their dreams. Posing as a kindly salesman to take them under his wing, he lures them into traps where he reveals his sharp teeth and devours them alive. When he encounters the young hero Jack, the Salesman murders the real Mr. Fisher to steal his identity and takes Jack on a game of cat and mouse, murdering and eating his friend Samantha. When he catches Jack at the end, the Salesman gloats over all the evil he's done over the years and how many dreams he's devoured before chopping off Jack's arm, planning to eat him and force Jack's mother to partake.
Kevin from "The Hard Goodbye" (with a short cameo in "That Yellow Bastard") is a young, cannibalisticserial killer who acts as a hitman for Cardinal Roark when he's not murdering and eating prostitutes — and he eats them piece by piece, keeping the women alive as long as possible and making them watch, as evidenced when he got his hands on Lucille, Marv's parole officer, who was found by Marv and survived, but lost one of her hands to him before the two escaped, ending up as the trope codifier for forced to watch. However, he gets one of the most gruesome, over-the-top, terribly long, and yet poetic punishments imaginable from the sociopathic hero Marv...even then, he smiles all the way to the end while being eaten by his pet wolf to deny Marv the pleasure of victory or revenge, and when Marv saws off his head to finish him, he doesn't give out a single scream.
Roark Junior from "That Yellow Bastard" is the son of a US Senator with the appearance of a handsome young playboy. In reality, he is a sadisticpedophile with a penchant for raping and murdering preteen girls and who loves the sound of screaming. These horrible crimes are covered up by his corruptSenatorfather (brother of the aforementioned Cardinal, natch), which means that no one on the police force is willing to take him down until John Hartigan saves his latest victim, Nancy Callahan, and goes through eight long years of prison for it because of the vengeful Senator dad. Near the end, it's revealed that Roark Junior is impotent unless he hears little girls scream in pain and that there were hundreds of victims.
The Colonel, also known as The Salesman, is one of the top enforcers in Herr Wallenquist's Basin City Mob. He runs a clandestine division of contract killers and occasionally performs the hits himself. He mentors new trainees to shed all redeeming traits so they can become remorseless killing machines, inducing one of them into murdering the only man she ever loved before assigning her the code name "Blue Eyes". His largest operation is the "Human Resources" division, a massive kidnapping, sex slave-trading, brainwashing, organ harvesting and industrial-strength porn production operation. He kills off one of his own henchmen through eye scream on the off chance that the hero Wallace might track the minion down, after previously having the man's male lover stabbed to death with over a dozen knives. He has an alliance with a dirty cop named Leibowitz, but when Leibowitz's loyalty might falter, he orders his son's arm broken as a warning and threatens to kill his whole family. The Colonel is pretty obviously a sociopath who displays no character traits other than hinting at a wish to direct the bodies of the people around him, to see their "full potential" realized.
Mammon operates as The Man Behind the Man to the devil Malebolgia. A Fallen Angel known as the lord of The Forgotten Ones, Mammon desired to create the perfect Hellspawn to assist him in ascending to rulership of all creation. To this end, Mammon haunted the bloodlines of Al Simmons and Wanda Blake, sowing death and destruction to create more Hellspawn and always leaving corpses and ruined lives in his wake. Mammon proves himself to be Spawn's greatest, most intelligent and most dangerous enemy, condemning the souls Spawn would seek to protect to hell to use them as leverage for their loved ones, and making deals to consolidate his power. When Satan returns and is furious at Mammon for claiming the throne, Mammon gets back in his former master's good graces by proposing to detonate the San Andreas Fault to kill and add the souls of many mortals to Hell's legions. After Satan is removed, Mammon unveils his master stroke- with heaven and hell sealed off from the world, Mammon sets about to conquer it from behind the scenes with Spawn's demonic daughter Morana, the product of his grand ambition.
In life, Billy Kincaid was a sadistic child killer. After being freed from jail, he lured a small girl into his ice cream truck and then murdered her. He then proceeded to chop off the girl's fingers and glue them onto a board as a trophy. After Spawn discovered Kincaid's brutal crimes, he killed Kincaid, sending him to hell. Dead, Kincaid became even worse than ever, given the task by Hell to gather more souls for them. Kincaid did this by possessing people and making them act out their worse impulses. This resulted in the murder of dozens of innocent people and the damnation of several more people to Hell, though Kincaid was having far too much fun to care. Kincaid also delighted in torturing the souls of children, especially one young boy part of the 'legion' inside of Spawn himself.
Clown/Violator was Spawn's Evil Mentor, sent by Malebolgia to train Spawn to be a solider in Hell's army. However, rather than train Spawn, Violator had a tendency to commit horrible crimes, such as ripping the hearts out of random mob bosses, just for fun. Later, Violator kidnapped Cyan, the 3 year old daughter of Spawn's widow Wanda. Violator framed Spawn for the kidnapping and then tried to kill Cyan by giving her a glass of poisoned milk. Spawn rescued Cyan and killed Violator in his clown form, sending him back to Hell. Violator later returned from Hell and possessed Jason Wynn, turning him into a Serial Killer. Wynn, under Violator's influence, would hire prostitutes that looked like Wanda and then murder them. Violator eventually gained complete control over Wynn's body and used his powers to turn random citizens into "clowns," transforming them into Brainwashed and Crazy psychopaths. Violator then ordered his clowns to go an violent rampage, resulting in massive property damage and several deaths. Violator later saved the life of a man of Barney Saunders, but this was no act of charity. Violator needed a new body to possess and chose Saunders. After possessing Saunders's body, Violator uses his powers to force the residents in Saunders's apartment complex to commit horrible crimes, including murder. Violator was able to use the violence in the apartment complex to further empower himself and then attempted to open a portal to Hell, which would allow his demon brothers to wreak havoc on Earth.
The Fall of Brek Zarith: Shardar is especially nasty, deciding that rather than just surrender his rule to the rightful heir to the throne, it's better to poison his own court and destroy all his treasures, leaving the kingdom bankrupt, hoping that, to restore it, the new ruler will be forced to become as big a tyrant as him, while he escapes and plans to start new conquest, using the psychic powers of the baby he kidnapped.
The Guardian of the Keys: Volsung of Nichor, a Dirty Coward introduced and killed in the third album of the series, is brought back to life by evil lesser deity, Nidhogg, who turns him into a perfect doppleganger of Thorgal. The deal is simple - he will seduce another deity who happened to have a soft spot for Thorgal, the titular Guardian, steal her magic belt, and bring it to Nidhogg, who will return him to his real form and grant him new life. Volsung steals the belt, returns to Midgard, kills Thorgal, takes his place, and, using magic powers of the belt, takes over the control of his village, murdering the current chief, rapes his wife, and threatens to smash the head of Thorgal's baby daughter, all to destroy Thorgal's good name and avenge his own death...that he had brought upon himself - Thorgal's only crime was being there when Volsung got himself killed, he hadn't move a finger to help it and couldn't have stop it in any way.
The Unfunnies: Troy Hicks intentionally turns a cartoon world into a horrifying Crapsack Worldfor shits and giggles. He knows they're not just drawings, since he switched places with a poor sucker from that world to escape death row, where he was on due to his being a child molester/killer.
Noriko, known as the Blood Princess, has had homicidal tendencies since childhood, where she would always beat her cousin Tomoe in spars to inflict as much pain as she could. In the present day, Noriko runs a mine, using slaves that have been press-ganged into service and worked to the point of death. Should any slave falter, Noriko promptly beheads the nearest one to serve as a morale-booster for the others. When she captures Tomoe, Noriko delights in treating her as a slave and when Tomoe refuses to perform the labor, Noriko furiously cuts down a random slave woman. When Tomoe immediately obeys to stop more death, Noriko sneers at her for caring about those of low birth. To conceal the mines, Noriko plans to blow it up, with every slave inside after all its resources are gone. She also reveals that she and Tomoe are actually ''sisters'' and when their father refused to acknowledge Noriko as his daughter, she murdered him, just as she had the man who raised her for for being weak. She reveals this while savagely beating Tomoe, taunting her that it's Tomoe's fault that he died.
General Fujii was the head of a gang that took over a village. They reduced the workers to slaves, and ordered them to farm and cultivate for long hours. They would continue to do this until the tax collector came, at which point they would just kill all the villagers and go to another town. When Usagi infiltrates them, he's discovered and tortured, with Fujii taking his swords. When the peasants revolt, the slaughter their way through them, and Fujii abandons most of his men to die or face the police. He and his loyal Dragon take over another gang and launch raids on a village, where he almost murders the elderly headsman for refusing them. When the heroes attack the gang to take him down, he abandons his dragon to run. He is such a bastard that even the aforementioned gang becomes repulsed by him. Usagi actually repeatedly calls him a "monster".
The Governor is an insane despotic leader of a small town of survivors, who feeds any survivors from outside the town to the zombies in order to keep them docile so he can run "fights" between people in his town with the zombies surrounding them. And this is only the start of all the sick shit he does during his run in the series, which includes raping one of the main characters repeatedly, leaving his own daughter (actually niece) "alive" as a zombie so he can keep her as a pet, and being responsible for the deaths of the vast majority of the cast in issue #48.
When the protagonists first encounter Thomas Richards, he merely comes across as a nerdy, polite and ultimately harmless inmate imprisoned for tax evasion. This makes it all the more shocking when he's revealed to be a homicidal lunatic who was really imprisoned for dismembering his wife for no reason at all besides his own enjoyment. Thomas decapitatedtwo little girls, Hershel Greene's twin daughters, Rachel and Susie, and ,taking advantage of the confusion surrounding his murders, attempted to decapitate Andrea as well. While he failed in his attempt, he ended up scarring her in the process. Eventually captured, when the community looks like they're going to execute him, Thomas is rescued by a woman he had befriended earlier named Patricia. Believing that Thomas is insane, not evil, and in need of psychological help, Patricia plans on the two of them escaping together. In thanks, Thomas immediately tries to strangle her to death. Though a minor antagonist in the grand scheme of things, Thomas acted as a dark harbinger of what was to come by showing how much worse humans could be than zombies.