Super Saiyan 3 (超サイヤ人 スリー) is the third form of Super Saiyan, the successor to the first and second transformations. Goku was the first to achieve the form, and was able to do so after several years of vigorous training in Other World. In video games, Vegeta achieves the form through a combination of extreme rage and rigorous training, and Broly achieves his version of the form through a large Zenkai.
Usage and Power
Super Saiyan 3 is the most powerful transformation a saiyan can undergo without the usage of God Ki. Goku uses the Super Saiyan 3 transformation in a brief battle against Majin Buu in order to stall him long enough for Trunks to find the Dragon Radar. He was able to overtake the monster, completely outmatching him blow for blow. He eventually retreated from the fight, as he wanted Goten and Trunks to defeat Buu with their fusion technique, as he "wouldn't be around forever." Goku later stated he believed he could have killed Buu if he had actually tried, but held complete faith in Gotenks' ability to destroy him if they were to try the Fusion Dance.