King Kai (lit. "King of the Worlds") or North Kai (lit. "North Kaio" or "North King of the Worlds") is a deity, the ruler of the North Galaxy, and Goku's final martial arts teacher, and later mentor. His planet is at the end of a long winding road known as Snake Way, where he teaches powerful, new techniques such as the Spirit Bomb and Kaio-ken. Despite the fact that his planet is around 100 feet in diameter, its gravity is ten times greater than Earth's. He has a monkey named Bubbles and a motor-mouth grasshopper named Gregory. He wears Teashade sunglasses, and owns a Red 1955 Chevrolet Bel Air Hardtop. He has a "strong sense of humor" and tells very bad jokes, although he possesses great wisdom and knowledge about the universe.