The Death Mage Who Doesn’t Want a... it just began, but the mc seems to go in that direction, and with reason.
most of korean novel have crazy MC .......................................................................................................
Please let there be a revenge tag.... For the most obvious, Light Yagami from Death Note... Dungeon Seeker I suppose? Crazy about not being human anyway.
The Beginning, Then End And Everything in Between in Royal Road. This one is awesome, it's one of my favourite. The MC is a serial killer and is sent in another world with OP stats. Unlike a lot of anti-hero, she's a real psycho, she doesn't kill for a good reason, she kills just because she likes it. She's pretty much the vilain of the story. It's dark humor, but if you don't mind, then you'll love it. Another one that I love is The Whiperer of the Nightingale (also in Royal Road). Once again, the MC is an assassin. After dying, she was reborn in another world. At the beginning, she may seem normal (besides the fact that she's quite mature, considering the fact that she kept her memorie), but seeing the way she execute her revenge is pretty... beautiful :3 There is also Dragon Princess (also RRL) or Dragon Princess Reborn (this one is a new version). MC is the daughter of two gods and definitely lack common sense. Her parents are even worse it's hilarious (I mean, they did destroy a whole world because they were pissed). Another RRL one: Beyond. The MC isn't crazy crazy, but still crazy. Same with his girlfriend. I mean the girl litterally ripped appart someone and the guy broke the legs of someone just because they were pissing them of. A lot of Xianxia Chinese novels have a crazy insane MC too. Like in Descent of the Phoenix – 13 Years Old Princess Consort or Congratulation Empress.