"You a big pest! You leave!"
Majin Buu throws his arms forward and fires a bluish-green energy wave against the opponent. He then charges more power into the energy wave, changing it into a giant energy sphere that blasts the opponent away, inflicting huge damage. Majin Buu uses this attack to defeat Gohan after being released from his Sealed Ball. The attack nearly kills Gohan, but Supreme Kai dispels the "Vaporize!" energy sphere before it blasts Gohan into space, landing him in a nearby forest. A little later, Majin Buu also uses a similar attack during his fight against the Super Saiyan 3 Goku, but fires it with one hand.
Appearances in games
The attack is named Mightiness Bomber (マイティネスボマー) in Dragon Ball Z: Super Butōden 3 and Dragon Ball Z: Hyper Dimension, Spread Ball in Super Dragon Ball Z, and it is also used in Dragon Ball Z: The Legend. It was named Vaporize! in the Raging Blast games, as one of Majin Buu's Super Attacks. In Super Butōden 3, Majin Buu can use a weaker version called Ki Bullet. Majin Buu also uses it as an energy orb in Dragon Ball: Tap Battle, under the name Buu Energy Orb.
In Dragon Ball Xenoverse, it appears under the name Innocence Cannon and is one of Majin Buu's Super Skills. It can also be obtained by the Future Warrior as a reward in Parallel Quest 36: "Majin Banquet".
"Fires a large Ki Blast that knocks the opponent back a great distance if it hits."
— Dragon Ball Xenoverse 2 Tutorial description
In Dragon Ball Xenoverse 2, Innocence Cannon returns as one of Majin Buu's Super Skills which can be learned by the Future Warrior (Xenoverse 2) by completing School Quest: "Lesson 2" of Majin Buu's Training.