Goku Meets Boo! (孫悟空魔人ブウに接触！ Son Gokū Majin Bū ni Sesshoku!, lit. "Son Goku Contacts Majin Boo!") is the four hundred seventy-third chapter of the Dragon Ball manga.
Goku begins teaching the Fusion Dance to Trunks and Goten. Goku orders Trunks and Goten to transform into their Super Saiyan states, and then instructs them to let out their complete power. Wishing to show off how strong he's become, Trunks becomes eager and powers up, with Goten following. Observing the training, Piccolo shows disbelief at how strong the two boys have become, while Goku is not as impressed, confusing Trunks. Realizing Trunks is the stronger of the two, Goku orders him to lower his power level to match Goten's.
Trunks complains at this order, but Goku replies that he has no time to disagree with Goku's methods. All of a sudden, Babidi transmits another message into the minds of all the people of Earth, including the Dragon Team. Still seeking revenge against Goten, Trunks and Piccolo for assisting Vegeta during his battle with Majin Buu, Babidi informs everyone that has learnt the location of one of his targets, Trunks' home in West City, and demands for Trunks to show his presence or else he'll assure that Buu leaves nobody alive once they visit. Knowing that her parents and Trunks' grandparents are still in West City, Bulma pleads to Goku to go down and rescue them. Goku requests that Bulma allow them to be sacrificed, so that he can continue to train Goten and Trunks. He assures her that he'll revive them with Dragon Balls, but Bulma still disapproves of this notion, reminding Goku that the city itself will be totally annihilated, meaning the deaths of millions, not just her parents. Goku says he'll restore the city with their second wish, but Piccolo reminds Goku of the wish made a few days ago, to restore the lives of the people killed by Vegeta at the World Martial Arts Tournament. Goku suggests using their second wish instead to wish for Earth to return to its state before Buu was released. Interrupting Goku, Bulma informs him that they cannot make any wishes, as they cannot find the Dragon Balls without the Dragon Radar, which is in West City. Concerned, Goku quickly changes plans, and orders Trunks to fly home and retrieve the radar before Babidi reaches the city. Goku informs him that he'll fend off Buu and Babidi so they do not reach the city in time. Questioning if Goku can hold off Buu, Trunks zips from the Lookout and heads straight toward West City and his home. Meanwhile, Goku uses his Instant Transmission technique to confront Buu. Just before Goku teleports, Buu and Babidi are making their way to West City, with Babidi showing his disapproval of Buu's speed, yelling at him to slow down or else he'll fall off. Buu grows to show his irritation at Babidi's complaints, but stops dead in his tracks when Goku materializes right in front of them.
Goku floats, calm and focused, whilst Babidi shows his surprise, believing Vegeta had killed Goku in their battle. Goku compliments Buu on his unmatched power, admitting that both he and Vegeta were wrong to doubt his abilities. Babidi immediately changes the subject, demanding to know the whereabouts of Piccolo, Trunks and Goten. Goku bluntly tells Babidi that he isn't here for that purpose, but is instead there to offer them both a firm warning. He notifies Babidi that his targets shall indeed show themselves, but only after completing their training to defeat Buu. Buu and Babidi both laugh loudly at the idea, with Babidi humorously expressing his doubts that anyone, let alone his targets, could defeat Buu with any amount of training. Goku smirks back, as Babidi continues to scream with laughter. Cutting his laughing session short, Babidi refuses to abide by Goku's rules, and once again demands their presence, or else they'll kill people even quicker. Goku informs Babidi he knew that'd be his reaction, and now prepares himself to stall Buu. Babidi giggles, and demands Buu to finally finish off this nuseance. Buu however, is day dreaming and playing in the skies, not listening to anything Babidi is shouting at him. Goku takes notice of Babidi's treatment toward his servant, and asks Buu why does he still obey Babidi and listen to his constant, demeaning insults. Buu himself pauses, and begins to ponder on Goku's point. Babidi threatens Buu with sealing him away back in his cocoon prison, but Buu retorts and says Babidi will not do that, because Goku could easily kill him without Buu in the way. Babidi realizes that Buu's intelligence is growing, and begins to fret over this development. Buu however, wishes to kill Goku, so obeys Babidi's demand, but only for the enjoyment of killing good guys. Goku realizes that he has no choice, and needs to face Buu in combat to continue stalling him. Goku transforms into his Super Saiyan 2 state, as Babidi and Buu look on. Babidi giggles again, recalling Vegeta's transformation into that same form and how it didn't help him. Goku realizes that he now needs to use his back-up plan, a form that goes beyond the form beyond the original Super Saiyan in order to even stand a chance against Buu's might.