Hanzō

also known as was a legendary ninja who was the former leader of Amegakure. He was very security-conscious, being guarded twenty-four hours a day and having anyone who wanted to see him thoroughly searched. He became famous around the time of the Second Great Ninja War. Little is known of his abilities aside from his riding on the head of a giant salamander (presumably a summon), but he was so powerful that he with his summon fought off all three Sannin. After their battle, he was so impressed with their strength that he decided to leave them if they agreed to accept the title of Konoha's ; This makes him responsible for the naming of the trio's title.

Hanzo's insecurities later got the better of him when a group of ninja, lead by Yahiko, Nagato, and Konan began a quest to end war through unorthodox means. He viewed these ninja as a threat to his power and sought to get rid of them. He then teamed up with the ANBU Root's leader Danzo to kill the groups leader Yahiko.

He was later single-handedly killed by Pain (under unknown circumstances), who took over and is the future leader of Amegakure. Every friend, family member, and acquaintance he had were systematically killed as well.

Trivia
Hanzō may have been named after a famous ninja Hattori Hanzō.

dead