Red Ribbon Saga
During this series Goku goes under training with Master-Roshi, later Krillin joins Goku in training. Master-Roshi teaches Goku and Krillin the dreaded Kamehameha. Later Goku gets trained again by Karin in his high tower, but this time his training was used to defeat Dr. Gero and to defeat Tao Pai Pai, a professional murderer that has killed one of Goku's new friends. After all this training Goku, Krillin, and Bulma, get together to get the Dragon Balls and Goku finally destroys the whole Red Ribbon head-quarters on his own.
Piccolo Saga
The series starts of as Goku enters the Tenkaichi-budokai, during this tournament Goku meets Tien and Choazu.The final match is between Goku and Tien, but Goku loses in this battle (due to an unfair, but cool ending)! Goku and Tien are falling in the air, and the first one to fall is the loser! so they are both very tired, so they can't do anything about falling. So Goku hits a truck, and falls quicker than Tien. After the battle Krillin is murdered, Goku starts looking for the killer. Meantime Piccolo is causing terror around the world. In a battle with Piccolo, Tien is about to die, when suddenly Goku arrives and defeats Piccolo. Before Piccolo dies, he gives birth. Knowing that Piccolo gave birth, Kamesama trains Goku. At the next tournament Goku battles Piccolo and defeats him, sparing his life at the end. At the end of the series Son Goku marries Chi-Chi.
Baby Saga
Ten years after the end of DragonBall Z, Goku gets turned into a child again by a wish Pilaf made. The only way Goku can get back in his normal state is by finding the Black Star dragonballs scattered across space. Goku, Pan , and Trunks go on journeys battling minor villains. At one planet, the DragonBall gang stumbles across Baby. Baby sneaks on board and lands on Earth. Baby takes over bodies in hope of finding a good host. Baby first uses Goten and Gohan as hosts, but he finally finds the most powerful host, it is Vegeta! Vegeta now turns into Baby-Vegeta. A great battle between Goku and Vegeta begins. It turns out Goku is no match for Baby-Vegeta. Then Kaiousin pulls out Goku's tail, hoping he can go into Oozaru stage. It works, but Goku still cannot defeat Bebi-Vegeta, who now is Super Bebi (Oozaru Bebi-Vegeta). Then something weird happens, Goku takes control of his body now and transforms into SSJ4 Goku! Goku soon defeats him.
Super A 17 & Evil Shenlong Sagas
In hell, Dr. Gero and Myuu creates Artifical 17. Artifical 17 comes from hell to fuse with Android #17, when they fused, they became Super 17. Goku gets tricked into going to hell to fight Cell and Frieza, who was already dead. Without Goku, the earth is doomed. Piccolo, (who died in the Baby Saga) and Dende creates a portal so Goku can get out of hell. Goku later kills Super 17. When the dragonballs are gathered to wish back the people killed in battle something goes wrong. Shenlong says that with all the negative energy the dragonballs have restored, seven evil dragons have been formed. Each dragon possess a dragonball, so Goku and the Z fighters go off to fight the evil dragons. When they come up against Li, SSJ4 Son Goku fuses with SSJ4 Vegeta! Making SSJ4 Gogeta. He beats the stuff out of him with ease. But Gogeta's fusion span was shortened because of the 4th stage of Super Saiyan. They can only stay fused for 20 min instead of 30 min. Just when Gogeta was about to finish Li, he diffuses. But the 2 warriors eventually killed the worn out Li. When all seven dragons have been defeated, the real Shenlong appears and grants Goku one wish, the wish is that everyone killed in battle against the dragons to be brought back to life. Shenlong tells Goku to get on his back, then the seven dragonballs are absorbed into Goku, and his whole body vanishes, leaving only his clothes on the ground. Seems that Goku is the most powerful fighter in the universe to have them absorbed.