After Gohan gives Goku the Senzu Bean, Koola wants to fight Goku, and discover the true strength of the legendary "Super Saiyan." Koola shows Goku how he defeated Piccolo. The changeling dropped the namek and just when Goku was going to catch him, Koola blows him up. All you see his smoking body falling towards the ground. Goku gets mad now. Sauzer tried to punch him, but he was unfazed. Goku powered up, which knocks Sauzer out of the way. Goku charges towards Koola and punches him. He knocks him into the water, where they had an underwater battle until Goku threw him out the water. Koola lands on a rock by the waterfall (as does Goku) and tells him he's impressed with his power and sees how Frieza was easily defeated. Koola does his 4th transformation and starts to whip Goku's butt like no other. Goku fought valiantly using Kaioken and later Kamehameha. Koola knocks the saiyan into a mountain wall and stomps him into it some more. Goku thinks about how he let his friends down. He grabbed a bird that landed in his hand. Koola was about to destroy Earth when he was stopped by Goku's yelling. Goku than transforms into (dramatic pause) a Super Saiyan. Goku appeared behind Koola holding his left the changeling's left arm and Koola is wondering where he came from. He punches Goku in the stomach, which had no effect. He began to power up and let the tyrant have it. Koola shoots a big ki blast right in Goku's face, and flies higher to form his own "Death Ball". Koola lets the blast loose, Goku catches it with his bare hands. However, he cannot withstand the immense power, and begins to collapse under it. Koola is pleased until he sees Goku blasts the ball right back at the changeling along with the Kamehameha, and Koola is hurtled through space. Koola realized he was the soft one for not killing Goku when he was a child. He is blown into the sun, and no traces of him.