Goku's Ancestors

Goku's next task in King Kai's training is to hit the grasshopper, Gregory, with a heavy mallet. After a long chase, it seems that Goku can't hit Gregory yet. While taking a break, King Kai tells Goku about the Saiyan people. They were a warrior race who shared Planet Vegeta with the smarter, though weaker, Tuffles. After a long war, the Saiyans overpowered and destroyed the Tuffles and stole their technology. The Saiyans became space pirates and began cleansing planets of civilizations and selling them. Eventually, the Saiyans' and Planet Vegeta were destroyed by a meteor shower, though only four Saiyans were able to survive; Goku/Kakarot, Raditz, Vegeta and Nappa. Willing to stop the Saiyans from destroying Earth, Goku continues his training and manages to hit Gregory. Now King Kai will train Goku himself in the ways of the Kaio-Ken.