In the seven years that pass after Gohan’s victory over Cell, the young man more or less puts martial arts behind him. As a result, he’s defeated pretty easily when Majin Buu hits the scene. Luckily, Old Kai, who Gohan accidentally frees when breaking the Z Sword, has an ability that can bring every last drop of power in his body out to the surface. With that, Ultimate Gohan — also known as “Mystic Gohan” — is born. His debut is positively ferocious, as he humiliates Buu’s latest stage, Super Buu, with next to no effort. Gohan’s cockiness gets the better of him, however, as his deliberate delay in vanquishing Buu allows the evil being to add Gotenks’ and Piccolo’s powers to his own, dramatically flipping the fight back in Buu’s favor.
Regardless, Gohan’s “Ultimate” state is undeniably impressive. It’s all the power from his two Super Saiyan forms and then some drawn out into his base form, essentially making transforming into a Super Saiyan or Super Saiyan 2 redundant. Better still, as long as he keeps his training up, his Ultimate state remains his default form, meaning he never has to waste energy changing into it. However, Gohan doesn’t continue training regularly after Buu is defeated, and he later goes to Piccolo for help in bringing out the transformation again. Visually, it’s not as showy as Gohan’s other forms, and it mixes poorly with his latent Saiyan ferocity when first used, clouding his judgment.