A Is the greatest hero in the world and is considered the Symbol of Peace and Izuku’s advisor. Born as incompetent like Izuku, he inherited the One For All powers from his master, Shimura Nana while studying at U.A. He was trained by Gran Torino before going abroad to study abroad to temporarily stay away from All For One’s control after the criminal killed his master. Toshinori can use One For All to transform into a muscular form that looks like an American comic superhero. Toshinori named himself All Might, a secret of his powers known only to a handful of people, including Headmaster Nezu, U.A’s Recovery Girl nurse and several professional heroes. Five years before the start of the series, All Might defeated All For One in a battle, but he suffered a severe wound, devastating his body to the extent of his limited time using One For All. He was down to three hours. This forced All Might to find a worthy successor while joining U.A as a teacher, he chose Izuku when he saw his courage and passed on to him One For All. Eventually, when his use of One For All was reduced to a few seconds, Toshinori retired to focus entirely on teaching while continuing to teach Izuku.