An arm for Luffy
Shanks won't take Luffy along, saying he's too young, and laughs when the boy eats the Gum-Gum Fruit the crew had stashed. When the bandit Higuma pours a drink over his head in the bar, Shanks laughs it off, and Luffy is furious with his hero. He only loses his cool when Higuma kidnaps Luffy. Higuma escapes by boat with the boy and throws him into the sea, where a Sea King appears. Shanks dives in, saves Luffy and loses his left arm to the monster, which he scares off with a single look.
As he leaves, Luffy says he'll become a pirate and King of the Pirates. Shanks puts the straw hat on his head and asks him to return it once he's a great pirate. Years later, in Orange Town, Buggy the Clown reveals the two were apprentices on the same ship and blames Shanks for making him swallow the Chop-Chop Fruit by accident and lose a treasure.