"I can feel all my supreme ancestry and the great leaders that have lead the Saiyan race flowing through my veins. This form, its power, it is inconceivable"
Super Saiyan 6 is a form that succeeds SSJ5. It's Vegeta's exclusive form and one of his most powerful. His suit changes into black training clothes. His hair is that of Super Saiyan 3, only longer. His tail is also the rich, golden color. This form proves to be accessible only to very high-ranking members of the Saiyan race, like Vegeta. In order to access this form, a Saiyan must have a SSJ3 form. Then he must look deep inside of himself, and uncover his ancestry. If you reach a certain memory that proves your a high-ranking member, you initiate transformation, and transform into SSJ6. Goku looked deep inside of himself, but found no traces of high-ranking members, rendering him unable to transform. Although this form has higher power than SSJ5, a Saiyan must use his Super Saiyan 3 form to transform. In this form, SSJ6 Vegeta can spar evenly with Super Saiyan 5 Goku and Gohan, meaning that SSJ6 is twice as strong as SSJ5.