The Buu Saga initially aimed to make Gohan the main hero of Dragon Ball, and it didn’t let go of this desire completely until the series was almost over. Upon achieving his “Ultimate” form, Gohan becomes the strongest non-fused character in the anime, and he could have easily defeated Super Buu and saved the day if Toriyama wanted him. This isn’t how things played out, however, and the future of Dragon Ball would look very different if they had.
Gohan killing Super Buu at the end of Dragon Ball Z wouldn’t change his role in the series, but it would change the lives of his friends and family. An early death for Buu would mean a very different ending to DBZ, and several characters not being present in Dragon Ball Super. Arguably, the biggest change would be to Dragon Ball DAIMA, as it would gain an entirely new protagonist.
Gohan Defeating Super Buu Would Remove the Need to Revive Goku
Fat Buu Would Never Join the Z-Warriors & Uub Would Not Exist
During the fight between Ultimate Gohan and Super Buu, Earth’s savior holds a decisive advantage towards the beginning. Had Gohan’s power-induced ego not gotten the better of him, he would have been able to easily kill Super Buu before Buu absorbed Piccolo and Gotenks. In this scenario, Gohan would do his father proud, and prove that Goku was right to allow him to take his place as the world’s protector. The trade-off for this would be that Goku wouldn’t come back to life in the wake of Buu’s defeat.
In the Buu Saga, Goku never shows any interest in returning to the land of the living for good. He proclaimed at the end of the Cell Saga that his presence on Earth only attracts villains, and he sticks to that way of thinking. The only reason he comes back to life at the end of the series is because Gohan loses to Super Buu. Old Kai revives Goku, so that he can work with Vegeta to succeed where Gohan failed. Gohan’s victory would mean there’s no need to bring back Goku.

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The Z Fighters would still have wished Vegeta back to life, especially after Bulma heard about his heroic sacrifice. For better or worse, the Dragon Team is terrible at holding grudges, especially where Vegeta is concerned. bWhile Vegeta would still be around on Earth, the same would not be true for Fat Buu. Super Buu was born from the fusion of Fat Buu and Evil Buu. Gohan killing the big bad without first expunging his good half would mean that Fat Buu would be killed, and would never join the Z-Warriors.
In the short term, this just means that Mr. Satan won’t be able to hold on to his title as World Martial Arts Champion for much longer. Mr. Satan being denied his part in the fight against Kid Buu, however, means he wouldn’t be on good terms with the Dragon Team in Dragon Ball Super, even if Gohan and Videl still wound up together. The total absence of Kid Buu in this narrative would also mean that Uub, his human reincarnation, would never be born.
Gohan Would Not Become the Star of Dragon Ball Super
Goku Would Remain the Logical Choice For Super Saiyan God
Set in-between Dragon Ball Z and Dragon Ball Super, Dragon Ball DAIMA has little to do with the rest of the franchise’s main story. It would be impacted by Gohan’s defeat of Super Buu, though, as Goku wouldn’t be around to serve as its protagonist. Rather, since Gohan would be both alive, and the warrior who killed Majin Buu, he would be the one Arinsu would work to lure to the Demon Realm.
Given how easy an adventure this series provided for Goku, not much would likely change in practice because of this, apart from Glorio and Panzy being given fewer headaches. In the Battle of Gods Saga of Dragon Ball Super, Goku would be forced back into play, and would naturally re-take his place as the series’ protagonist. This comes down to the fact that Beerus would still wake early and come to Earth looking for a Super Saiyan God, and 6 righteous Saiyans would still be needed to make one.

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It’s theoretically possible that the Earth wouldn’t fall into danger. Buu wouldn’t be present to enrage Beerus by not sharing his pudding. It’s likely, however, he’d grow bitter over not finding a Super Saiyan God sooner or later, and become a threat. To prevent the God of Destruction from destroying Earth, the Dragon Team would have no choice but to revive Goku.
With Goku likely surpassing Gohan through his non-stop training in Otherworld, given Gohan’s preference for living a normal life, he would still be the one chosen to become a Super Saiyan God. From that point on, Goku’s battle with Beerus, and the entire Resurrection ‘F’ Saga, would play out identically to canon.
Team Universe 7 Would Have Different Rosters During Dragon Ball Super’s Tournaments
The Removal of Fat Buu From the Z-Warriors Makes Room For Other Fighters

In the canon Universe 6 Saga, Fat Buu is recruited alongside Piccolo and Monaka to join Goku and Vegeta in the Tournament of Destroyers. Fat Buu no longer exists in the scenario where Gohan killed Super Buu, meaning Goku would be tasked with finding a replacement for him. Goku respected Gohan for his dedication to studies and preferred not to involve Goten and Trunks in tournaments.
Knowing that Krillin and Android 18 were also no longer interested in fighting, this would leave Goku with only Master Roshi and Tien Shinhan as viable options. As seen in Dragon Ball Super‘s Universe Survival Saga, Goku has a much stronger preference for working with Roshi, meaning the Turtle Hermit would be recruited. Of course, who gets chosen doesn’t ultimately matter, as both would simply fall in an instant against Hit, following Vegeta’s loss to the assassin.

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The only difference Gohan killing Super Buu would make to the Future Trunks Saga would be that Goku and Vegeta would have no experience with Fusion. In the Buu Saga, the two only ever formed Vegito so they could surpass Buuhan. Vegito’s presence in the Future Trunks Saga doesn’t matter much, though, so this isn’t too big a deal. Where things get more interesting is the Universe Survival Saga. In Dragon Ball Super, Fat Buu is part of Team Universe 7. His sudden slumber right before the Tournament of Power, though, is what forces Goku to act without thinking, and revive Frieza.
If Goku had known in advance that he was down a fighter, he wouldn’t ultimately do something so rash. He would have seen the perfect 10th team member fairly recently. Using the Dragon Balls, Goku could wish Future Trunks back into the main timeline, and request his help. With Future Trunks having already seen his own timeline erased by Zeno, he’d naturally agree to help prevent Goku’s from meeting the same fate.
Several Arcs of Dragon Ball Super Would Never Take Place
Moro and Gas Would Be Goku’s Final Opponents Before the Dragon Team Got Their Happy Ending
Future Trunks is powerful enough to fill Frieza’s role in the Universe Survival Saga, and Team Universe 7 would still win the Tournament of Power. However, Frieza not being revived in the Universe Survival Saga would have a massive impact on the rest of the series. The Galactic Patrol Prisoner Saga would mostly stay the same, apart from Buu no longer having a role in it, but things would diverge following this point.
With Frieza still dead and in Hell, the events of Dragon Ball Super: Broly would never take place, and Goku and Vegeta would never meet the third full-blooded Saiyan. The events of Dragon Ball Super‘s Granolah the Survivor Saga would mostly play out the same but, with no Black Frieza around, Goku and Vegeta would be forced to finish the fight against Gas themselves. None of these changes would affect or impact Dragon Ball Super: Super Hero.

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The film would be anti-climactic, however, as Cell Max would be the final opponent that the Z-Warriors had to overcome. No Black Frieza would mean that everyone would simply get to relax and enjoy themselves following Cell Max’s defeat. This is fitting in a way, as Gohan would thus kill both the final villain of DBZ, and the final villain of Dragon Ball Super. The “End of Z” would also play out differently from canon.
Uub would no longer exist, meaning that the 28th World Martial Arts Tournament would be naturally completed, and that Goku would remain with his family, like he had for the previous 10 years. Goku would still be interested in training an apprentice who could one day give him an incredible fight though and, based on her behavior in Dragon Ball Z, Pan would actively desire to fill this role. This means the end result of Goku’s son being the one to defeat Super Buu would be Goku training his granddaughter to follow in his and Gohan’s footsteps.
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Dragon Ball tells the tale of a young warrior by the name of Son Goku, a young peculiar boy with a tail who embarks on a quest to become stronger and learns of the Dragon Balls, when, once all 7 are gathered, grant any wish of choice.
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