I might have found Wolverines ultimate weakness

A big rock. Get him under a rock. He won't die but he ain't moving or lifting it.

Or Rogue, she could prolly kill him. Or Ice-man could freeze him solid and then put him in the freezer. Or any telekenetic could just squash and scramble his brain. It'll heal, but he ain't doing much when his brain is upside down in his skull.