North Kaio

King Kai (界王 Kaiô, literally, King of the Worlds) or North Kai (北の界王 Kita no Kaiô, literally, King of the Worlds of the North) is a Hero in Dragon Ball Z and Goku's final martial arts teacher, and later mentor. He also taught Piccolo, Tien Shinhan Yamcha, and Chiaotzu. 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.

Saiyan Saga
King Kai first meets Goku when Goku journys to King Kais planet to seek his traning King Kai teaches Goku the Kao Ken attack which doubles the users power and a red auroa which surroneds them.

Frieza Saga
During the Frieza Saga King Kai trains Piccolo Tien Shinhan Chiaotzu Yamcha.

Students

 * Goku
 * Piccolo
 * Tien Shinhan
 * Chiaotzu
 * Yamcha
 * Olibu
 * Majirone
 * Many others Aliens