Master Roshi is the loveable old pervert who was the childhood teacher of Krillin and Goku. He is the first person to master the Kamehameha, and taught it to his students. He trained in his younger years with Chi-chi's father, The Ox King, under the supervision of Goku's adoptive grandfather, Son Gohan. He was once the strongest fighter on Earth, winning numerous Bodukai's under the disguise of Jackie Chun. His arch rival was Tien and Chaozu's teacher. After being killed during a battle with Piccolo during the Dragon Ball series, Master Roshi mainly just sits on the sidelines now as a source of comic relief with all his porno mags, and a place for the Z Crew to go in between adventures.