Anti-Hero: Type IV but struggles to be a Type III. He goes after mobsters and criminals, enjoying the suffering he is giving them. Also while he'll never harm innocent people, his unstoppable rage doesn't stop him from breaking the fingers of an Asshole Carny while incognito.
Berserk Button: Don't call Darkman "freak", try to cheat him out of a carnival prize, or as noted below, the surgery that keeps his burns from being unbearably painful had the side effect of giving him a lot of these.
Blessed with Suck: The treatment that cut off his pain, allows him to be super strong and tough, but also makes him prone to severe mood swings.
Cursed with Awesome: However, he does possess superhuman strength, durability, and agility caused by the surgery. Once, he was able to adapt the surgery procedure, he was able to kick a lot of ass and escape mostly without injury.
In Return of Durant, it is shown that while Darkman prefers to be alone, he doesn't mind giving back a basketball to a kid that lost it.
While he hates Rooker in Die Darkman Die, he doesn't take it out on his wife or child. In fact he goes out of his way of revenge protecting them. In the end, he actually sacrifices the only stable synthetic skin to fix the kid's face when he could have used it on himself.
Genius Bruiser: As a scientist he makes strategies for his attacks on Durant and his gang.
He Who Fights Monsters: He is the first superhero to admit that he would end up like that. The scene where Pauly has been killed, he's sitting on top of a building saying "What have I become? What have I become?"
Improbable Aiming Skills: Thanks to his adrenaline rush, he is not only strong, but has excellent aim. As proven when during a minor bout of stress he managed to win a carnival game with the baseball during the first film.
Large Ham: "JUUUUUUUUUUUUUUUUU-LIEEEEEEEEEEEEEEEEEEEEEE!!!" and "SEE THE DANCING FREAK! ONLY 5 BUCKS! STEP UP AND SEE THE DANCING FREAK, JUST 5 BUCKS!"
Made of Iron: Darkman can get hurt, but since he's lost all sense of touch, tends to ignore it.
Manipulative Bastard: In the first movie he was able to fool Durant and his cronies to believing Pauly stole their money. In the second movie, Durant caught on to his disguise trick. However rather than it giving him an advantage, it made Durant paranoid that any of the mooks could be Darkman. He went as far as tugging a guy's face to make sure he wasn't Peyton.
Master of Disguise: Slowly became one over the course the first Darkman but more or less perfected it by Return of Durant.
Mood-Swinger: Despite his status as a hero his amplified emotions cause him to swing from one to another. As Darkman he goes from a raging psychopath to a crying baby. Even as Peyton he is too overly happy almost border-lining to slasher smile material.
Ooh, Me Accent's Slipping: Liam Neeson's American accent slides all over the place, till the point where you can hear his Ballymena accent coming in.
Required Secondary Powers: Since Darkman is missing roughly 40% of his skin, he pretty much needs a Healing Factor, or he'd keel over from various horrible diseases and the injuries he sustains in battle.
Westlake also seems to be the worlds greatest vocal impersonator. Also a talented ventriloquist as he somehow manages to speak coherently without lips.
Ambiguously Gay: At least to his minions in the first film. During a meeting with a couple of goons, one of them mentions that Durant may have a thing for Rick after Durant congrats Rick after killing Yakko.
Chekhov's Skill: He claimed that before he became head of his company that he started out as a High Steel worker. This made him skilled enough to keep balance on the beams while fighting Darkman, who was struggling not to fall off.
Faux Affably Evil: For the most part, he initially seems genuine with his feelings towards Julie and wants to help her out. In reality, he's a greedy Manipulative Bastard willing to do anything to make his dreams a reality.
Strack: What do you think, Julie? Who's the real monster here? I destroy, to build something better! Whereas you? You're a man who destroys for revenge! Look! Look about you! It's all mine! Because I built it! I built it all!