Why was the Genki Dama able to defeat Kid Buu?

[Analytical Delusion]

So I've been rethinking this recently, and the progression of the perception of what it takes to totally defeat Buu is interesting.

We first see Buu regenerate from brutal blows. Vegeta then decides he needs to vaporize Buu to kill him. No dice. Buus bits come together to reform him.

Piccolo went back to the site of the explosion, and saw Buu reforming. So in the RoSaT, he and Gotenks make sure to destroy the pieces of Buu. This time, he regenerates from the smoke created.

Somehow, the Genki Dama is able to succeed where these attempts failed. Is it just much more powerful? Is it the fact that it's 'genki' instead of ordinary ki, and something to do with its ability to eliminate evil? Was Buu surrounded so the bits and smoke couldn't escape? Something else?

Could SSJ3 Gotenks or Ultimate Gohan have obliterated Buu? Or even Vegetto? Buu took heavy damage from all three, but without a technique like the Genki Dama, do we know for sure you can annihilate Buu? A line that was interesting:

Chapter: 514 (DBZ 320), P5.3
Context: as pure Boo beats up on good Boo some more
Vegeta: “…This is bad…Have you noticed, Kakarot?...The fatso’s power is falling…If it’s Boo against Boo, then he can take damage…”

Vegeta seemed shocked. Is the implication that a non-Buu can't deal permanent damage/drain stamina from a Buu? Or maybe it's the case that Buu has such a stamina advantage, but if a non-Buu opponent is strong enough, he can overpower Buu's stamina/durability advantage?

[Cipher]

I always thought it was just strong enough to vaporize him in one go--something no one else had done up to that point. (Though Gotenks, Gohan, and certainly Vegetto may have been strong enough to.) This is backed up, I think, by Goku suggesting he may have been able to defeat Boo in their first fight, or that he could defeat Boo in the Kaioshin Realm as a fully powered-up Super Saiyan 3. After saying that, he never expresses anything along the lines of, "Oh, never mind. Only this one particular kind of technique can do it!" It's just his only way of gathering sufficient power in the moment.

As far as Vegeta's comment, I just took that to mean that if Boo's opponent shares his resilience, he's eventually going to be outdone and won't be able to keep undoing the damage.

[hunduel]

Same goes for Super Cell vs Gohan's Kamehameha. Cell literally could regenerate from anything, yet a simple attack vaporized him so much that nothing remained from him. The same happened here.

Plot Device.

[Analytical Delusion]

I always thought it was just strong enough to vaporize him in one go--something no one else had done up to that point. (Though Gotenks, Gohan, and certainly Vegetto may have been strong enough to.) This is backed up, I think, by Goku suggesting he may have been able to defeat Boo in their first fight, or that he could defeat Boo in the Kaioshin Realm as a fully powered-up Super Saiyan 3. After saying that, he never expresses anything along the lines of, "Oh, never mind. Only this one particular kind of technique can do it!" It's just his only way of gathering sufficient power in the moment.

As far as Vegeta's comment, I just took that to mean that if Boo's opponent shares his resilience, he's eventually going to be outdone and won't be able to keep undoing the damage.

Goku's belief that he could defeat Buu as a full-powered SSJ3 (which evidently he could not access while alive) is a counterpoint. He also told Vegeta they could use the fusion dance (to become a hypothetical manga Gogeta) to defeat Buu. It is worth noting though that Goku didn't see the attempts by Vegeta (was knocked out) or Gotenks (didn't have the crystal ball out yet). He did see Buu self destruct and come back of course.

Same goes for Super Cell vs Gohan's Kamehameha. Cell literally could regenerate from anything, yet a simple attack vaporized him so much that nothing remained from him. The same happened here.

Plot Device.

Yeah I think out-of-universe it's clearly a way to make the next villain's regeneration more OP than the last. Cell was able to regenerate a ton more than we understood Namekians could to that point, as long as that one core in his cell was intact (of course, we later learn after Trunks breaks the Piccolo statue created by Dabura, that as long as his head was intact, he could regenerate). I think in a sense, Buu's regeneration was intended to be a step up from Cell's. I'm practice though, that creates a lot of confusion of what exactly the conditions for defeating him were.

[KBABZ]

I always figured it was down to pure volume in addition to its power; for its size and mass, the Genki Dama used by Goku was enormous and dense enough to wipe out every particle of Buu, and it being designed specifically to annihilate evil would have helped it a lot as well. It's relatively close in size to the one he used on Frieza, but it contained a lot more energy.

I've also always had a sneaking suspicion that Toriyama might have intended to end the conflict at Vegeta's sacrifice but decided to keep it going, which I think happens more than once or twice after that (and I also feel that the opposite happened at the very end; he was wanting to set up a new arc but then decided "You know what? I'm done"). I kinda feel he did that with Cell too, and brought Cell back to face Gohan again for a more climactic ending to his defeat.

[Analytical Delusion]

Actually, re-reading the strength checker, came across this:

Chapter: 492 (DBZ 298), P5.7
Context: after Boo regenerates from being hit with the Super Ghost Kamikaze Attack
Piccolo: “Shi…Shit…damn it! Rather than burn [the pieces of Boo’s body], we should have completely wiped them out with our ki…!”

That suggests that it wasn't the good vs evil property of the genki-dama, but just that it did a better job of wiping out Buu - and opens up the possibility that someone else (Gotenks, Gohan, Vegetto, or SSJ3 Goku) could've done the job.

[mute_proxy]

Same goes for Super Cell vs Gohan's Kamehameha. Cell literally could regenerate from anything, yet a simple attack vaporized him so much that nothing remained from him. The same happened here.

Plot Device.

Cell could regenerate as long as his "core" stayed in tact. Gohan's attack was strong enough to destroy the core (it was literally shown) along with Cell. Know your facts.

[KBABZ]

Actually, re-reading the strength checker, came across this:

Chapter: 492 (DBZ 298), P5.7
Context: after Boo regenerates from being hit with the Super Ghost Kamikaze Attack
Piccolo: “Shi…Shit…damn it! Rather than burn [the pieces of Boo’s body], we should have completely wiped them out with our ki…!”

That suggests that it wasn't the good vs evil property of the genki-dama, but just that it did a better job of wiping out Buu - and opens up the possibility that someone else (Gotenks, Gohan, Vegetto, or SSJ3 Goku) could've done the job.

Which is what I was alluding to when I was talking about the sheer volume of the Genki Dama.

[precita]

It may also be due to the fact that the moment Kid Buu was killed he was reincarnated as Uub as a wish to King Yemma.

[Wizard Sesame]

and I also feel that the opposite happened at the very end; he was wanting to set up a new arc but then decided "You know what? I'm done").

What set up for another arc do you see in the final Buu parts?

[Analytical Delusion]

Actually, re-reading the strength checker, came across this:

Chapter: 492 (DBZ 298), P5.7
Context: after Boo regenerates from being hit with the Super Ghost Kamikaze Attack
Piccolo: “Shi…Shit…damn it! Rather than burn [the pieces of Boo’s body], we should have completely wiped them out with our ki…!”

That suggests that it wasn't the good vs evil property of the genki-dama, but just that it did a better job of wiping out Buu - and opens up the possibility that someone else (Gotenks, Gohan, Vegetto, or SSJ3 Goku) could've done the job.

Which is what I was alluding to when I was talking about the sheer volume of the Genki Dama.

Good call, you were right I believe.

What was the issue with Vegeta's self-destruction then? It wasn't the size of the blast. I guess it was only powerful enough to blast Buu to bits, but not powerful enough to wipe him out completely?

[KBABZ]

and I also feel that the opposite happened at the very end; he was wanting to set up a new arc but then decided "You know what? I'm done").

What set up for another arc do you see in the final Buu parts?

Personally I see it in that it begins at the Budokai again after a major timeskip (which was used to start the Tien and Majunior arcs, and Buu to a lesser extent). Then it got a few Chapters in until the story abruptly ends. I dunno, it feels familiar and like it could lead into a new arc, but then the story ends at that point early on instead.

Note that I don't claim this to be hard undeniable fact; it's just a personal theory.

What was the issue with Vegeta's self-destruction then? It wasn't the size of the blast. I guess it was only powerful enough to blast Buu to bits, but not powerful enough to wipe him out completely?

No idea! If I were to hazard to apply reasoning to it, I'd say that A) Vegeta's sacrificial blast wasn't powerful enough, and/or B) the energy explosion/sphere was wild and didn't have the same density as a Genki Dama. To use a comparison, Vegeta's sacrifice is like the Eraser Tool in Photoshop with a noise filter turned on, while the Genki Dama is when it's just an all-erasing circle with no opacity. If that makes sense...?

[Kamiccolo9]

Vegetto was able to destroy parts of Buu with that shockwave thing. It was probably just because the attack was powerful enough to wipe out all of Buu.

[Darkprince410]

Actually, re-reading the strength checker, came across this:

Chapter: 492 (DBZ 298), P5.7
Context: after Boo regenerates from being hit with the Super Ghost Kamikaze Attack
Piccolo: “Shi…Shit…damn it! Rather than burn [the pieces of Boo’s body], we should have completely wiped them out with our ki…!”

That suggests that it wasn't the good vs evil property of the genki-dama, but just that it did a better job of wiping out Buu - and opens up the possibility that someone else (Gotenks, Gohan, Vegetto, or SSJ3 Goku) could've done the job.

There's never been a good vs. evil property of the Genki Dama. Outside of an individual with no evil within them whatsoever having the ability to deflect it if they know to do so (as with Gohan), nothing has ever been said or even suggested that the Genki Dama has more or less effect on someone depending on the level of evil they have.

[sintzu]

Actually, re-reading the strength checker, came across this:

Chapter: 492 (DBZ 298), P5.7
Context: after Boo regenerates from being hit with the Super Ghost Kamikaze Attack
Piccolo: “Shi…Shit…damn it! Rather than burn [the pieces of Boo’s body], we should have completely wiped them out with our ki…!”

That suggests that it wasn't the good vs evil property of the genki-dama, but just that it did a better job of wiping out Buu - and opens up the possibility that someone else (Gotenks, Gohan, Vegetto, or SSJ3 Goku) could've done the job.

Which is what I was alluding to when I was talking about the sheer volume of the Genki Dama.

Good call, you were right I believe.

What was the issue with Vegeta's self-destruction then? It wasn't the size of the blast. I guess it was only powerful enough to blast Buu to bits, but not powerful enough to wipe him out completely?

Vegeta had taken a massive explosion and beating from buu before so he wasn't at full power when he self destructed. I think he could've killed him had he not fought and instead blew himself up from the start or at least after blowing that hole in him.

[dbgtFO]

I think it would have worked visually better, if it was like, when Vegeta was hit by the Genkidama. It didn't just detonate immediately, but seemed to be constantly electrocuting him before finally blasting into space. That way we'd understand that all Buu's molecules were being destroyed.

But I basically think that's what happened, the blast enveloped Buu and obliterated everything.
Fat Buu survived against Vegeta because his pieces were just blown away, but not destroyed.

[sintzu]

It is worth noting though that Goku didn't see the attempts by Vegeta.

I think had Goku known about what happened with Vegeta he wouldn't have used Ssj3 as Vegeta was able to hold him off with 2.

[Lord Beerus]

I've always thought that Genkia Dama was just simply much stronger compared to previous attempts especially since there were more stronger people contributing to it.

Same goes for Super Cell vs Gohan's Kamehameha. Cell literally could regenerate from anything, yet a simple attack vaporized him so much that nothing remained from him. The same happened here.

Plot Device.

Cell could regenerate as long as his "core" stayed in tact. Gohan's attack was strong enough to destroy the core (it was literally shown) along with Cell. Know your facts.

And yet when Goku destroyed the top half of his body, where is core is located (in his head), he still regenerated.

[mute_proxy]

And yet when Goku destroyed the top half of his body, where is core is located (in his head), he still regenerated.

He changed the location, I dunno ¯\_(ツ)_/¯ a continuity error

[Lord Beerus]

And yet when Goku destroyed the top half of his body, where is core is located (in his head), he still regenerated.

He changed the location, I dunno ¯\_(ツ)_/¯ a continuity error

More like a flat out plot hole.