Zaraki D. Taiga

Zaraki D. Taiga is known by his desire to fight strong opponents, but is more known because of his insanity. In almost every battle he is asked if he has any sanity, and the only thing he does is to answer his signature phrase: "Sanity? Sorry, but I don't remember having such a useless thing in the first place". He thought that he was the strongest when he was still in East Blue, but when he went to the Grand Line he was only barely wining, and was overwhelmed by a Pacifist, barely runing away. After he recovered, he went training for 2 years, he came back even more insane, and with power that would crush everything, after eating the Boko Boko no Mi.