Batman shows Blood Knight tendencies at times. He often tries to make himself not enjoy the violence he inflicts upon criminals, but some pleasure does seep through as this quote from War Crimes shows:
Batman: Still, doing it this way does have its compensations. My fists fit so nicely into their guts. And impact meat and bone with perfectly satisfying thumps.
All-Star Batman & Robin, the Boy Wonder: Frank Miller takes this side of Batman to an outrageous character breaking degree as Batman is literally burning criminals alive and then having sex with Black Canary because he feels so alive.
Though she's more often than not portrayed as affectionate, reasonable and a force for peace, being raised by combat-ready Amazonians since she was just a little girl has had this effect on Diana. It's fairly common to see her smiling broadly while fighting demons, gods and any super villains dumb enough to challenge her. The New 52takes this even further as shes shown having a whale of a time-fighting Darkseid, gleefully slaughtering criminals and she even becomes the Goddess of War herself. However, it's subverted as the effects of becoming a god take a heavy toll on Diana leading to some Freak Out! moments for her. DC Rebirth dials it back making Diana much less blood thirsty although shes still more eager to hack villains apart with her Cool Sword than her colleges/friends Superman and Batman would like.
Cheetah literally lives off this trope as Barbara Minerva serves the Goddess of the Hunt and seeks to glorify the deity by killing any Worthy Opponent or prey which puts her at odds with Wonder Woman who usually desire peace. Whenever Cheetah teams up a super villain team her only real goal is to kill Diana and she couldn't care less for planet conquest, unless it spoils her hunting, she even collects the skulls and bones of her prey as trinkets. Her ending in Injustice 2 has her forcing Brainiac (before beheading him) to create a world where she can hunt and kill freely without interference.
Ares naturally. He became Diana's biggest enemy because he is a counterpoint to her efforts to prove mankind is worthy of protecting. Par for the course Ares lives off conflict and fighting him especially on a battlefield will power up to him up. After agreeing to stop trying to incite wars and influence humans he even restyles himself the The God of Conflict to get power from any conflict in Wonder Woman (1987). Being the embodiment of war means he has plenty of weaknesses, specifically The Power of Love and when war is non-existent on Earth (e.g Injustice) means Ares is super weak and on verge of death.
In New 52, Ares isnt villainous or blood hungry at all and plays the Mentor Archetype to Diana.
Artemis unlike Diana who (outside the New 52 and Rebirth) prefers to avoid conflict and fighting when at all possible and often talks her opponents down or uses her lasso to make them realize the horror of what they've done/are trying to do Artemis on the other hand absolutely loves a good fight. She will charge in and turn a situation into a brawl even if a peaceful resolution is at hand. After some character development she backs down a little from this but she'd still prefer fighting to talk to her opponents.
In Gotham City Garage, Big Barda from the New Gods has spent years trying to break free from Granny Goddness' indoctrination, but even so she's never happier than when she fights.
Barda: Highfather help me. Even after all there years away from Granny's Forge... I'm never as at home as I am in war.
Supergirl is quick-tempered, fierce and proactive, and several writers have interpreted her hotbloodedness as a passion for fighting. In Justice League United, the team runs into a gathering of bounty hunters and Kara is giddy because she has to punch them.
Green Arrow: Sardath said this space station was a bit rough... be ready for anything. Supergirl, I hear voices through that door, can you see through it with your X-Ray vision? Supergirl: Oh... This is going to be fun! Green Arrow: Hmmm... What is it, Supergirl? A few alien thugs? Supergirl:[smiling] No. Much better than that... Bounty hunters. Lots of them. Animal Man: ... Oh Crapballs.
Reign, a member of Supergirl's Rogues Gallery, loves to fight and she's very good at it.
Mongul II is merely one of these at his very best. The arrogant, fight-loving asshole side, however, is almost always supplemented with some of the most disgusting behavior in the DCU. He bit off more than he could chew, however, and holy shit did Sinestro make him pay for it.
The one-shot "Mogo Doesn't Socialize" gives us a bounty hunter by the name of Bolphunga the Unrelenting, who hunts down the titular Green Lantern for the fun of it. He ends up... well, relenting... on realizing that Mogo is a planet.
Lady Shiva has been both protagonistand antagonist depending on the storyline. The only constant to her character is that her life revolves around becoming and remaining the best martial artist she can possibly be — and proving it over the unconscious or dead bodies of as many other "A-List" DC martial artists she can possibly pound on. She had a brief fling trying to be a Mentor figure for Black Canary and Tim Drake.
In Mastermen #1, Leatherwing of Earth-10 espouses that he only believes in "What's real, dirty... and leaves bruises." His "interrogation" of the Human Bomb included beating him with a baseball bat, and overall he feels similar to the Batman of All-Star Batman & Robin, the Boy Wonder.
Deadshot, oh so much. Lampshaded by his then-lover Jeanette when she says that one of her previous husbands was "A mad dog killer who pretended it was for money" and goes on to say that he was probably a bit LESS single minded than Deadshot.
Catman and Scandal are also very much this trope, and King Shark certainly skirts it as well.
The Comedian of Watchmen gleefully admits that he is also partially this trope along with mostly Psycho for Hire. It's at least to an extent a product of his worldview, as he seems to act this way mostly because he acts the way he feels the world actually is. However unlike truer examples he doesn't take it lightly into being slashed, brutalized and on the receiving end since for him it is less about the challenge and more about thrill-killing.
Rorschach as well, his thought bubble upon seeing a rapist accosting a woman in front of him, only to look around and see him is simply "Sometimes the night is generous to me".
Avengers arch-foe Kang the Conqueror. He was a native of a peaceful age in humanity's future. Kang thought peace was boring, so he donned a futuristic combat suit and used Time Travel to become a conqueror of all time and space.
The Champion: This member of Marvel's Elders of the Universe is this trope personified. Each of the Elders remains immortal through single-minded pursuit of their particular monomania. The Obliterator also fits the description, is dedicated to the destruction of living things..
All the Dark Avengers (except The Sentry, Moonstone, and maybe Marvel Boy). The rest of them just love to hunt and kill or beat the everloving shit out of real heroes.
Bullseye dear christ, even among the vilest of Marvel's Rogues Gallery he stands out as Ax-CrazyPsycho for HireSadist who makes the likes of Doctor Doom and Norman Osborn look sane and rational. Bullseye takes vicious (sometimes sexual) delight in combat like when impaled Elektra with her sai, and once threatened to murder his Arch-EnemyDaredevil's family, all his ninja friends "then have a sandwich". Bullseye also takes pride in his killing and his main beef with Daredevil is the fact he made him miss.
Deadpool: He punched Kitty Pryde to try and get Wolverine mad enough to fight him and was extremely happy when the claws came out, yelling "Snikt me! Snikt me!"
Deadpool: Yay, now is fighting time, fighty time, blood blood blood!
Spider-Man. No, seriously. Peter enjoys fighting as Spider-Man so much that sometimes, in early comics Spidey even showed disappointment at the common Mooks who can't do much more than "tickle" him. He even holds back the majority of the time because just knocking thugs out would be too easy - and also dangerous (as Doc Ock discovers while controlling Peter's body, when he hits the Scorpion so hard he punches his jaw off). Earlier in his career, Spidey often picked fights with Human Torch, Wolverine, and even the goddamn Hulk just because he wants a good scrape - though in the latter case, it was because he'd hit the Despair Event Horizon after it looked like Mary Jane had died in a plane crash and wanted to feel some time again. While the Hulk was initially annoyed at Spideys attack he instead offered sympathy after realizing what had happened, having lost his own wife. In Nick Spencers run, Peter has an Enemy Without situation and the Spider-Man half is a complete Blood Knight, smashing villains and damaging New York simply for fun with no sense of responsibility that defines Spidey. Before Peter and Spider-Man fuse together again, Spidey tells his alter ego that he shouldnt be too ashamed of having some fun while crime-fighting.
It's actually quite poignant if you consider Peter was bullied for most of his childhood and was helpless to fight back - so in many ways Spider-Man was the outlet for his frustrations.
Kaine, Peter's clone, and the current Scarlet Spider remain this even after his HeelFace Turn. Before, it was a product of his mental instability and the constant agony he was in, both caused by the imperfections in the cloning process. Now, it's the remains of his dark side, plus the fact that he really does not believe in Thou Shalt Not Kill (when faced with someone sufficiently evil).
Carnage a true Ax-Crazy psychopath makes Eddie Brock look like the picture of mental health in comparison, Carnage butchers people with gleeful abandon, he even once misquoted Ben Grimm's catchphrase to fit his own sadistic style.
Carnage: Check out my Thing impression: "IT'S MURDERIN' TIME!"
Sergei Kravinoff aka Kraven the Hunter one of Spider-Man's greatest villains is also one of the biggest Blood Knights in the Marvel universe. In Africa, he hunted and killed every single animal that walks, crawls and slithers and had every intention of hunting Spider-Man down as well and does so with a passion. Spidey is such a Worthy Opponent to Kraven that failing each time to kill him just makes even more hell bent to destroy Spider-Man, even when with Sinister Six Kraven often complains, saying he "doesn't hunt in a pack" and would rather kill Spidey on his own. The Chameleon even asks his half brother why so cheery in face of Spider-Man's strength and Kraven answers, in true blood Knight fashion.
Chameleon: I don't get it, Kraven! You say he's far stronger, far more dangerous than you thought— and you're happy about it. Kraven: Of course I am, he's kind of foe I've always wanted— one to test my mettle to it's fullest! What triumph this will be for me! How sweet will be the fruits of my victory.
Kraven's Last Hunt is the penultimate example of Kraven's desire to conquer Spider-Man, after many years of failing. Kraven hunts down Spidey and seemly kills him and buries Peter in a grave. Kraven then dresses up as Spider-Man himself and hunts down criminals for a time but unlike Peter, he kills the goons he finds. Spider-Man then wakes from the tranquilizer Kraven shot him with and digs his way out of his grave and seeks out Kraven who explains he has conquered Spider-Man by proving he could kill him at any time as well be a "better" Spider-Man than him. Kraven then infamously commits suicide as he fulfilled his purpose, but comics being comicshe was resurrected.
The Mighty Thor loves fighting and proving his strength being very Hot-Blooded and has gone up against the strongest beings in the universe, though unlike other examples he's enough of a Nice Guy to settle things peacefully. However, when a challenge presents itself Thor can't help but heartily accept. Even when "unworthy" Thor still went all One-Man Army on hordes of beasts "fighting and failing... and fighting again".
The Incredible Hercules. He's the page picture for a reason. Not so much for the blood as Ares and toned down some from other appearances, but still loves to fight.
And then there's Ares, who's like Hercules but with less of a conscience. The two happen to be brothers as well.
Ares: I am sorry, Wonder Man! I cannot hear you over the sound of returning fire!
Incredible Hulk. Especially in his Greenscar, Joe Fixit, and Devil Hulk personas.
One of Hulk's villains The Abomination, retains his intelligence when transformed, meaning all the destruction and fighting he does has no Freudian Excuseand is purely for shits and giggles.
Castle: I caught a glimpse of heaven once... Then I was cast down. Back to a world of killers. Rapists. Psychos. Perverts. A brand new evil every minute spewed out as fast as men can think them up. A world where pitching a criminal dwarf off a skyscraper to tell his fellow scum you're back is a sane and rational act. The angels thought it would be hell for me. [said "dwarf" hits the ground with a splat] But they were wrong. Welcome Back, Frank. Says New York City.
This is only the tip of the Punisher iceberg. In The Punisher: Born, his origin story from MAX imprint, it's explained that Frank Castle was born Frank Castiglione, and changed his name to Castle because there was a limit on how many tours a solder could serve in Vietnam, and he wanted to go back for a third. During this third tour, Frank starts hearing a voice in his head egging him on to greater and greater feats of violence against his enemies, and taunting him with the fact that wars end, and eventually he would have to stop. The voice is never specifically explained, but it offers Frank a "war without end, for a price. All you have to do is say yes". Frank ignores the voice until it goes away, and goes about his mission. Later, his camp is overrun by 'Cong... while another soldier has ordered a napalm air-strike on the camp itself. As the bombs fall, the entire camp is incinerated as Frank says "YES". After the battle, all the Vietcong are dead, Frank's skin is covered in third degree burns, and he is standing in the middle of the bombed out camp, wielding an M16 with the butt smashed after bludgeoning several soldiers. The next scene is him coming out of the gate at an airport stateside, months after he has healed from his injuries. He goes to hug his family, when the voice returns for the first time, and says "Hey Frank... remember that price I talked about? Enjoy your time with them while you can."
And along the same line, both Nick Fury and Col. Rudi Gagarin in Fury (MAX).
The Thunderbolts once featured two of these as members: Scourge, formerly Nuke, a battle-crazed lunatic whose worst nightmare is a world without war, and Mr. X, whose empathic powers cause him to experience incredible bliss every time he kills. Mr. X reveled in the chance to go to Asgard during the Siege event — he wanted to prove he could kill a god. He could.
Wolverine is like this at least to some extent. The animalistic side of his psyche clearly does get pleasure from violence.
The Ultimate version of Wolverine seems to be this way or at least in Ultimate Wolverine vs Hulk. In it he's offered a chance to save a village in a far off country from the Hulk; he doesn't care about any of the people, he just wants a thrill from a fight.
X23 and Daken are also Blood Knights to mixed degrees, same as their dear father.
Sabretooth IS this. Easily the most bloodthirsty character in the MU besides maybe Bullseye and Carnage, he lives for nothing but the opportunity to be able to slaughter anything that it's practical to slaughter, and he'll usually also bag a few other prizes.
The Juggernaut is this too. He is compelled to revel in wanton destruction of his own making by the powers of Cyttorak that fuel his strength. In fact, if the Juggernaut isn't engaging in indiscriminate violence for the sake of indiscriminate violence, he actually gets weaker.
Beast may be a Genius Bruiser poet and Gentle Giant but due to his animalistic side, he falls into this trope occasionally. Its especially evident when hes facing the aforementioned Juggernaut and has a huge smile on his blue furry face before flipping Jugs over. Sometimes Depending on the Writer Hank more civilized but other times hes as enthusiastic about fighting as he is working on scientific discoveries.
Gambit, youd think a thief would be more subtle, but Gambit goes out of his way to have as much fun as he can in a fight and wont back down from even the likes of Wolverine and Sabertooth. Its best shown during the Claremont era when Gambit was once up against a pack of Skrulls pretending to be the Star Jammers and despite being completely outnumbered, when a huge female Skrull asked if really thought he stood a chance Gambit replied with a smile Now. Mamselle moren ever. Shall we Party?.
Psylocke is a reluctant example. She started out as a fairly standard hero with a slight ruthless streak and action junkie tendencies. Then she got her mind merged with that of a master assassin, then had her life saved by dark magic that twisted her personality towards darkness, then trapped a psychopathic psychic monster inside her head for a prolonged period, then got brainwashed into becoming the Horseman of Death, then was forced to kill pretty much everybody she loved in one form or another, then gave up her capacity to feel sorrow... after all of which she's still a hero, but now has to constantly struggle in order to not leave a trail of corpses in her wake. And when she finds an excuse — she enjoys it.
The Ultimates: Hawkeye grows to relish battle as a means of coping with his family's death.
Nemesis the Warlock: Nemesis himself is a bloodthirsty alien warrior who fights Torquemada primarily because he makes a good enemy.
Shakara: Warlord Skulka, Supreme Khan of the Xorn Empire, lives only to kill as many as he can manage, as he loves combat and destroying civilizations more than anything. In truth, he's become bored after he helped with the destruction of the Shakara, once the strongest species in the galaxy, as he doesn't feel anyone can match them.
Button Man: Harry Exton becomes a pretty notorious Button Man because he prefers to kill all his opponents, whereas wounding them is considered sufficient to win a match and actually preferred as it leaves the Button Man available for further matches.
Aquila: Aquila himself is an unstoppable war machine, but his "brother" The Spartan is an even better example. He was resurrected by the gods not because he prayed to them for mercy, but his sheer hatred from being denied the chance to kill again upon his own death impressed them so much that they turned him into an immortal warrior.
Judge Dredd: Dredd himself is happiest (or the closest he can come to being happy) when he's on the streets of Mega City One, busting heads. He notes that Mega City One is the most violent, evil city on earth, but he loves it. It's the main reason he keeps turning down the office of Chief Judge.
For a more jolly and lovable version, see Obelix in the Asterix books. ("I do hope Asterix explains this to me later, I generally like to know why we're fighting," just before KO-ing an entire village of other Gauls in Asterix and the Cauldron.) In fact, most of the village act like this ("Hey, boys a fight!" "Come on, it'll be a change to fight each other!" leading to an all-village brawl in Asterix in Spain, which would eventually become a Running Gag).
TheMidnighter from the Wildstorm series The Authority as he's about to destroy a city by ramming it with a 30 mile wide space ship aimed directly at the Villain of the Week:
Midnighter: I love being me.
Cindy of Cindy and Biscuit does avoid genuinely harming entities that don't seem to be hostile, but she's mainly driven by a largely unadulterated love of fighting monsters to the death.
Warren Griffith of the Creature Commandos was a werewolf. Though he's a sheepish coward in human form, his wolf form carries with it a primal bloodlust that is never sated. He's always looking forward to the next battle, and never satisfied when it ends.
Groo the Wanderer from the eponymous comic exhibits many of the characteristics: he will drop almost anything for a fray, and frequently chastises opponents who attempt to run away before he is finished slaying them.
In Gold Digger, the Murder Fist branch of the Shun Leep style makes its users into Blood Knights by putting them into a state of nirvana when in combat with a skilled foe. This inevitably drives them towards the Psycho for Hire category as they cease to care to exercise the control to not kill on purpose, while their skill continues to grow and grow from fighting powerful enemies.
In Invincible, Battle Beast brought peace and prosperity to his homeworld by beating the crap out of any and all threats. Unfortunately, he developed a taste for combat and left his world to seek out worthy foes. Unfortunately for him and just about anyone he fights, he's one of the strongest beings in the universe. So far, Thragg, the strongest Viltrumite alive, is the only one who has ever defeated Battle Beast by snapping his neck in an instant. And after he recovers, Battle Beast is eager for a rematch. When they do face again, Thragg gets his guts sliced open by a third party, not willing to accept any advantage Battle Beast cuts his guts open as well so it can be a fair match. Oh and the ensuing fight between Thragg and Battle beast lasted days, even Thragg had developed some begrudging respect for BB before killing him.
In Sin City, Marv admits that he loves a good fight. Miho apparently does as well. Actually, you can add Dwight and the Girls of Old Town to the list as well, see The Big Fat Kill.
Dwight: The Valkyrie at my side is shouting and laughing with the pure hateful bloodthirsty joy of the slaughter and so am I.
Like his video game counterpart, the titular Sonic the Hedgehog is this, though for a completely different reason (he gets bored and restless when there's no new challenge or threat, and will often deliberately go seeking one out). There's also E-123 Omega, who has gone so far as to unload his payload on a Physical God and complain when he still had ammo to hit him with. He's even fallen in love (or close to it) with Blaze the Cat because of her own actions!
Overlord never cared about rank, glory, or the advancement of the Decepticon cause... he was happy as long as he had the opportunity to fight and slaughter as many Autobots and bystanders as he could. Megatron, however, wasn't happy with that — upstart subordinates had given him too much experience with Chronic Backstabbing Disorder to take it on faith that someone with that much power wouldn't make a power grab. So when Megatron tried to tighten the leash and take more control over Overlord's actions, Overlord re-purposed Garrus-9 into a planetwide spectacle of violence and chaos to provoke Megatron into the one fight that Overlord has always wanted. He has a Villainous Breakdown and surrenders when he finds out Megatron is (apparently) dead.
In the Marvel Transformers comics, Bludgeon probably qualifies. He talks about a grand dream for the Decepticons conquering the universe but when they actually conquer a world... he's bored out of his mind and wondering when the Autobots are going to show up to stop them. And again when he invades planet Earth, he's bored out of his skull (no pun intended) because Optimus Prime doesn't show up to fight him like he hoped he would. One suspects that if there were no Autobots he either wouldn't give a damn about the Decepticons or their plans to take over the world, or would start the Autobots in order to pick fights with the Decepticons.
Overlord immediately breaks out of the Villainous BSoD he was stuck in after Last Stand of the Wreckers when he finds out Megatron isn't dead after all, meaning he might just get his fight.
Whirl's philosophy of life is, for the most part, that you should resort to violence both quickly and thoroughly. He never runs from a fight and goes on recreational violence sprees just for the hell of it.
Whirl: So this is what running away feels like? I'm not keen. It's like fighting, but in the wrong direction. Cyclonus: Rodimus told us not to engage. Whirl: He did, yes, he absolutely did. And I'm going to interpret that as a veiled order to attack... Care to join me?
In Usagi Yojimbo, Nakamura Koji is a swordfighter who goes around looking for worthy opponents to duel with. There are other such characters in the series too.
The protagonist of Spiritus, Kinju Dayal, is a world-champion MMA fighter. She took to the ring not necessarily to win, but to beat up her opponents as badly as possible. By all accounts she was very good at this.