Goku powers up to Kaio-ken x3 as he charges at the opponent and roundhouse kicks them up into the air. Then, he flies up in the air and punches the opponent away. Next, he flies up over the opponent and down behind to double kick them further up into the air. Finally, Goku flies up into the air around the opponent and hook kicks them down into the ground, inflicting a huge amount of damage.
Goku uses this attack during his first battle against Vegeta. After being dominated by Vegeta's increased speed and power even with his Kaio-ken x2, Goku decides to use his Kaio-ken x3. Goku charges up and his power soon surpasses Vegeta's, much to the Saiyan prince's shock. Activating his Kaio-ken x3, Goku rushes at Vegeta and attacks him with the Kaio-ken Attack, knocking him many meters away into a mountain.
Appearances in games
Kaio-ken Attack was named in the Budokai Tenkaichi video game series, where it is one of Goku (Early)'s Blast 2 attacks. In Budokai Tenkaichi 1 and Budokai Tenkaichi 2, the name was given to Goku's other Kaio-ken rush attack, Kaio-ken Finish; this was later fixed in Dragon Ball Z: Budokai Tenkaichi 3 and Dragon Ball Z: Tenkaichi Tag Team. The Raging Blast games and Dragon Ball Z For Kinect feature the Kaio-ken Attack and Kaio-ken Finish as separate attacks. It is one of Goku's Special Attacks in Battle of Z.
Under the name Kaio-ken Assault, this rush appears as a Super Move usable by the Future Warrior in Dragon Ball Xenoverse 2.