"The End of Super Saiyan 3" (超サイヤ人３消える Sūpā Saiya-jin Surī Kieru, lit. "Super Saiyan 3 Vanishes") is the three hundred eighteenth chapter of Dragon Ball Z and the five hundred twelfth overall chapter of the Dragon Ball manga.
The cover of this chapter shows the fat Majin Buu lifting a Dragon Ball platform on which stand Trunks, Mr. Satan, Vegeta, Android 18, Goku, Krillin, Gohan, Piccolo, Goten. This cover art is also featured in Daizenshuu 1 and as a menu screen in Dragon Ball Z: Infinite World.
As Buu continues to scream in agony on the Sacred World of the Kai, holding his head while panting loudly, Mr. Satan continues to taunt the monster, calling him a coward, and that he should tremble at the Champion of the World's feet. Goku, watching all of this, still trying to charge his ki to full power as a Super Saiyan 3, does not believe that Buu is actually scared of Mr. Satan, and something else must be occurring inside of Buu for him to start screaming in pain. Buu eventually stops screaming, and starts to spit something from his mouth, a small blob which turns into the unconscious fat Majin Buu, who Vegeta and Goku did not retrieve from Super Buu's stomach earlier on. As Mr. Satan shows his confusion, Kid Buu starts laughing, being free from the torture that the fat Buu inflicted on him from the inside to stop him from attacking his friend, Mr. Satan. On another planet, Dende (still watching the battle through a Crystal Ball), explains this information to Old Kai and Kibito Kai, with Old Kai replying that even if the small Buu attacked Mr. Satan, it would be no big loss, showing his dislike for Mr. Satan. Buu, now free from the fat Buu interfering, now walks slowly towards Mr. Satan, showing no remorse, only an evil grin. Mr. Satan, now showing fear, still holds his ground, and has slight confidence he can still win, still believing this is all a dream. Buu delivers a hard punch to Mr. Satan's nose, resulting in Mr. Satan comically rolling over the floor, while screaming and holding his bloody nose. Running a far distance away from Buu, Mr. Satan cowardly tries to intimidate Buu, stating Buu only has one more chance to apologize. Buu, not paying attention to Mr. Satan's demands, bangs his chest like an ape, confusing Mr. Satan, who claims this might be a sign of Buu's surrender. Buu however, still charges towards Satan, making Mr. Satan more frightful than ever. As he closes his eyes and covers his face, preparing for Buu's final strike, Buu is attacked by a small energy beam. Buu looks in the location where the beam came from, and sees the fat Buu, now conscious, standing tall, with an angry expression. Goku, Vegeta (now conscious), and Mr. Satan all look towards the fat Buu in surprise. the fat Buu informs the small Buu that he hates him, and orders the small Buu to leave Mr. Satan, his best friend, alone. As Mr, Satan starts to tear up at Buu's sentence, Kid Buu roars furiously, as the two Buus charge towards each other, resulting in Kid Buu managing to kick the fat Buu in the face. The fat Buu and Kid Buu continue their fight, as Fat Boo recovers from Kid Buu's powerful kick and manages to headbutt Kid Buu directly on the head, resulting in Kid Buu flying back many feet. Kid Buu then uses the Mystic Attack, grabbing the fat Buu by the antenna and slamming him into the ground, resulting in the ground collapsing from the impact and the fat Buu's weight. As the fat Buu stands back up, he fires a small energy ball at Kid Buu, managing to completely disintegrate Kid Buu's left arm and most of the left side of his chest. Kid Buu however, immediately regenerates, as the fat Buu becomes frustrated. Vegeta, still bleeding rapidly and holding his damaged arm, shouts at Goku for taking so long charging, stating he should have been done a while ago if all it took was a minute. Goku replies by stating something is going wrong, and it must be due to this being the first time he has ever used the Super Saiyan 3 form while alive, and that it is putting far too much strain on his body. Goku, now running low on energy, loses the Super Saiyan 3 form, and transforms back into his base form, shocking Vegeta, Dende, Old Kai and Kibito Kai. Meanwhile, Kid Buu and the fat Buu continue their brutal battle, Kid Buu charges towards the fat Buu at full speed, managing to completely obliterate the fat Buu's head and neck. As Mr. Satan looks in shock, the fat Buu regenerates, and continues to battle Kid Buu, but admits to Mr. Satan he will not win, but has to keep trying. Vegeta now deems the situation a disaster. With no energy left, Goku and Vegeta wonder what to do, as brutal force alone will not work against Kid Buu. The battle for the universe's safety is turning towards Kid Buu's favor, with all hope seemingly lost.