"Super Fusion Unleashed!!" (強いぞ！！ スーパーフュージョン Tsuyoi zo!! Sūpā Fyūjon, lit. "He’s So Strong!! The Super Fusion") is the three hundred first chapter of Dragon Ball Z and the four hundred ninety-fifth overall chapter of the Dragon Ball manga.
Gotenks calls Buu out of the crater, knowing that his attack wouldn't be enough to kill him. He tells Buu to hurry up since he won't be able to stay this strong for long, and it’ll be an hour before he can do it again. Piccolo arrives, and Gotenks says maybe he was too strong after all and Buu really is dead. But suddenly a huge blast shoots up from the crater, barely missing Gotenks and Piccolo. Piccolo nervously notes that the blast had enough energy to obliterate the Earth in an instant. Gotenks is mad and decides to fire some Continuous Die Die Missiles down into the crater. Piccolo warns him that he'll blow up the Earth, but Gotenks isn't too concerned since everyone's dead anyway. Piccolo yells at Gotenks that he could end up destroying a Dragon Ball, and if even just one ball is destroyed, then nothing can be restored.
Gotenks stops, thinking Buu's probably been weakened anyway. Buu comes flying up out of the rubble, but not really weakened. Piccolo says he really is weakened; although not physically, but certainly in spirit. Buu's never fought anyone this strong before. Gotenks gloats and thinks Buu's scared, but Piccolo scolds him about being careless. Buu flies over and headbutts Gotenks off into the distance, and then chases after him. Gotenks dodges a punch and then hammers Buu into the remains of a city. Gotenks flies at Buu, but Buu shoots a huge mouth blast at Gotenks. As the smoke clears, an angry Gotenks appears, burnt to a crisp. He decides to counter with his own mouth blast, which fries Buu in return. The two take to the ground, and Gotenks gets in a kick, blocks a punch, and gets in another kick, before taking the upper hand and absolutely pounding on Buu. Goku thinks Gohan won't even get a turn at this rate. Gotenks announces he's going to finish this and bust Buu up into tiny little pieces, and he won't be able to recover anymore, because he'll wipe Buu out with his ki this time. But then suddenly, Super Saiyan 3 runs out and Gotenks return to normal…