Villains/antagonists or otherwise.
I’ve been watching some Fable 3 lets plays and was reminded of how much I absolutely hated Reaver. You can tell Lionhead was really going for someone that you would “love to hate,” but every scene with him in it is miserable. Absolutely ridiculous that you can’t kill him.
For a character from an actually well written video game, Eric in Tony Hawk’s Underground. Hitting the last line in the game and watching your character punch him out in a cutscene afterwards is extremely cathartic.
(in the 'written to be hated on purpose" category) Ted Faro from Horizon Zero Dawn, every time you hear his name, it goes “and then he did something worse” . Fuck Ted Faro. Also he’s literally Elon Musk, and that was years before he went full Nazi.