Kishibe from Chainsaw Man is the grizzled, stoic and somewhat unhinged last survivor of a whole generation of Devil Hunters. Despite his age and lack of contract-viable body parts, he’s still among the best-of-the-best, relying only on his honed skill set to take down the most dangerous superpowered devils. He’s a ruthless but effective mentor, as shown when he trains the pseudo-immortal Power and Denji by killing them over and over.
Source：https://www.cbr.com/anime-characters-similar-to-kishibe-chainsaw-man/
