Eustass Kid is notorious for causing huge amounts of civilian casualties. He is generally either angry or making sarcastic jokes. When he feels that he is being insulted, he is quick to resort to violence, as shown when he attacks someone for apparently staring at him. He is quite sensitive to being mocked, insulted, or glanced at. He also seems to be extremely cruel even when not provoked, as he crucified another defeated pirate crew just because he deemed them too weak to roam around.