Dragon Ball Z: Wrath of the Dragon

Gotenks and Buu continue their fight. Gotenks seems to be wearing Buu down, and he has the upper hand in the fight. Just as he's about to hit Buu with his final move, Gotenks returns to normal from his Super Saiyan 3 form. The power was too much for him to sustain. Buu begins beating up Gotenks, who is now much weaker. Gohan has finally finished his training, and is ready to return to earth. After saying goodbye to Goku for the last time, Kibito takes him back, and Gohan asks him to change his clothes. He's now wearing clothes just like Goku. He's arrived just in time, because Gotenks has separated.