The innocent Buu begins to attack the tall evil Buu, however as innocent Buu has lost most of his competitive spirit the evil Buu easily gets the upper hand. Innocent Buu usese his chocolate attack but it gets reflected back at him. Innocent Buu is now a piece of chocolate which Evil Buu eats creating a new Buu, with increased strength.
Meanwhile Goten and Trunks manage to perfect the Fusion technique, and head off to fight Buu. However even in their fused state they are still no match for him, so the return and train harder. Eventually they are able to fuse and maintain Super Saiyan status, however the 30 minute time restriction still means that they are not guarenteed victory.
Buu begins to destroy more cities until he feels the Ki of Gotenks, and flys up to God's palace. When Buu arrives Goten and Trunks are sleeping and are quickly taken to the room of Spirit and Time to train for their fight against Buu. Buu demands to fight Gotenks, but Piccolo manages to dely him.
Piccolo's delaying tactics work for 30 minutes, but Buu gets bored and wants to fight Gotenks now. Piccolo says he can when Buu has killed all the people on the Earth. The other Z-fighters look on amazed, but remember that the Dragonballs can bring back the human race. Buu powers up and sends out millions of energy blasts which kill everyone on the Earth with the sole exception of Hercule. Buu again demands to fight, so Piccolo takes him to the room of Spirit and Time by the longest way possible. As he walks he tells Trunks and Goten via telepathy that he and Buu are coming.
Trunks has an idea on how to have a good fight, Goten agrees and they work out their routine. Eventually Piccolo and Buu enter the room of Spirit and Time, and the fight begins. The kids fuse and the fight between Buu and Gotenks starts. Although Gotenks is strong, Buu is able to match him blow for blow. Gotenks has some new techniques, the most dangerous being the kamikaze ghost attack. No matter what attacks Gotenks uses against Buu, nothing seems to be working. After a heated battle Gotenks decides to turn Super Saiyan 3 but decides to make the fight more dramatic by pretending that he is powerless to do anything.
Gotenks begins to rant on how it is hopeless, Piccolo is amazed but realising the dangerous situation destroys the door leading out of the room of Spirit and Time. Gotenks is shocked and explains to Piccolo that he was only joking! Piccolo is mad, Buu is confused.
The three fighters are still adapting to their situation when Buu realises that by being stuck in the room he can no longer have chocolate! This makes him mad and he screams loud. So loud that he creates a hole allowing him to escape. Gotenks turns Super Saiyan 3 and creates another hole which he and Piccolo escape through. However the time difference gave Buu the chance to snack on the remaining Z-fighters. Gotenks continues the battle with Buu, and it looks like Gotenks will win. As the fusion begins to end, Gotenks insists Buu to hurry up as he can only stay this way for a little while. Buu hears this and decides to delay the fight as long as possible.