The great martial arts master and a kai-o-shin, King Kai is introduced in the very beginning of the Dragon Ball Z series. King Kai has a small planet at the very end of Snake Way in Heaven. After his death in the battle against Raditz, Goku travels down Snake Way to train under King Kai. Goku finally makes it and learns King Kai is opposesed with jokes. Cracking every bad joke in the book, Goku finds it hard to believe that this is the great martial arts master. King Kai teaches Goku the Kaio Ken attack and the Spirit Bomb. After Goku leaves to return to Earth, King Kai watches over the battle with his telepathic powers. After the battle against Nappa and Vegeta, King Kai is visited by the recently deceased Yamcha, Piccolo, Tenshinhan, and Chiaotzu. King Kai trains them for a long time (the entire Frieza Saga). After the four return to Earth, King Kai continues to watch over Goku and the others with his telepathy, advising them when he sees fit. Much later, during the Cell Games, Cell prepares to self-destruct. The explosion would destroy the entire planet. To save Earth, Goku teleports himself and Cell to King Kai's small planet. The explosion kills Goku, King Kai, and King Kai's pets Bubbles the monkey and Gregory the cricket. King Kai is granted an even bigger planet and he remains there for the rest of the series.
