Why didn't anyone else adopt Kaio-Ken?

[dbzfan7]

Excluding the numerous people who suggest it would make human characters relevant, I'm talking more of the stronger fighters. Piccolo, Boo, Oob, Cell, etc. If they used this ability they'd be ridiculously strong. We don't even know if Kaio-Ken X20 is the limit to how high someone can go, but even if it is, a bunch of people would still be ridiculously powerful with this technique. Piccolo would dwarf everyone of the group early on. Cell should know the move since the spy robot recorded Goku vs Vegeta, so he would have been unstoppable if he used it. Boo if taught this move would be an absolute monster, same with Oob. Then we have people like Beerus and Whis who would be like...super godly if they used it (unless it's incompatible with God Ki for some reason IDK). Perhaps if Goku and maybe Vegeta now have all this new power god power in base without strain, Kaio-Ken could boost them to insane levels. I always believed it wasn't used for SSJ since it still causes minor strain and SSJ does affect the body to some degree. But if pure unaltered specimen with high power levels use Kaio-Ken...then damn one shots for all (Cept Humans). Could this count as a bigger oversight then the Kienzan issue everyone seems to have?

[Herms]

Piccolo tells Gero that he and the rest of the gang all "amplify" their ki when they fight, and Goku likewise described the Kaio-Ken as "amplifying" ki when talking to Kuririn back in the Saiyan arc. So maybe everyone gets so good at the principles behind Kaio-Ken that it just becomes a natural part of their fighting style and stops being a special technique. A bit like how at first there's this special technique called "Bukujutsu" which Crane School fighters use to fly, then non-Crane School characters start learning Bukujutsu, and before too long every character can just fly as a matter of course, and hardly anyone bothers to call it "Bukujutsu" anymore. Maybe. That's what I tell myself to sleep at night, anyway.

[Kamiccolo9]

I'm just gonna go with Piccolo not having been at Kaio's long enough to learn the technique, and the Earthlings not being good enough or resilient enough to do so. I mean, it was tough on Goku, and he's way more resistant to stress than they are due to his Saiyan biology.

[Super Saiyan Turlast x4]

I just think the Kaioken quickly became a thing of the past once Super Saiyan was introduced. I agree that it could've been useful for other characters, but the technique in general just seemed to be overlooked completely. When looking at it from another standpoint, perhaps it was good that the Kaioken didn't become a technique everyone became familiar with like the Kamehameha. Still, it would've been nice if Cell told Krillin he was capable of doing both the Genki Dama and the Kaioken.

I always thought Piccolo's quote to #20 had a bit of a Kaioken aspect to it, too. Aside from that, I can just see him referring to them being able to power-up immediately once they begin to fight, which would explain why #20 was only able to drain his suppressed energy.

[Rocketman]

Piccolo was only there for six days, and the humans don't really fight enough after coming back for it to ever show up if they did have it. King Kai himself can't do the technique, so it's apparently not easy.

[Kakacarrottop]

It got majorly shafted in favor of "Super Saiyan" since that sold more merchandise, just like non-Saiyan characters got shafted in favor of Saiyan characters.

[dbzfan7]

Well besides Herms answer which is the type of hypothesis I want to see, I'm not asking for "Why did Piccolo not learn Kaio-Ken while with Kaio". That is not the question. I mean during all the free time where anyone could have Goku teach them this ability, why does no one do it?

During the 3 year training for the Cyborgs, Piccolo could have easily picked up the skill in that time frame. My issue is why no one ever tries to use this incredibly broken skill for high level fighers. For Saiyans it makes perfect sense since they have Super Saiyan and stuff, but for someone like Piccolo or Boo, they'd be ridiculously strong. I can see Boo passing it off as he doesn't care about being a fighter, but Piccolo for sure would have sought out Kaio-Ken as he'd be pretty powerful with Kaio-Ken X20 (or higher as nothing says he can't go higher). If 3,000,000 is the power level to handle x10 efficiently, then someone massively stronger should be able to handle X20 no problem and debatably higher levels if X20 isn't some kind of level cap.

Beerus and Whis could supposedly use this power too and be ungodly strong if God Ki works with it (Maybe that's why Kaio can't use it...though his ki can be sensed...hmmm). Cell should have no reason to not know this technique and if he used it, would have been unstoppable at the Cell Games. Gero knows of Kaio-Ken so Cell should know too and be able to replicate it.

[Angelus]

Seems like King Kai just didn't teach it. Goku was the only one who could teach but just didn't.

[singsing]

Seems like King Kai just didn't teach it. Goku was the only one who could teach but just didn't.

I think the question is why didn't Goku teach them.

[FoolsGil]

A better question would be why didn't anyone else adopt the Spirit Bomb? Even if Yamcha's, Chaozu's, and Tenshinhan's bodies could withstand levels of Kaioken higher than Goku, their powers would still be too low for anything outside of the guerrilla ambush.

[singsing]

A better question would be why didn't anyone else adopt the Spirit Bomb? Even if Yamcha's, Chaozu's, and Tenshinhan's bodies could withstand levels of Kaioken higher than Goku, their powers would still be too low for anything outside of the guerrilla ambush.

I agree. Then you can have the competent fighters stall instead of the people who are 1000x weaker than the enemy.

[dbzfan7]

A better question would be why didn't anyone else adopt the Spirit Bomb? Even if Yamcha's, Chaozu's, and Tenshinhan's bodies could withstand levels of Kaioken higher than Goku, their powers would still be too low for anything outside of the guerrilla ambush.

Even with Kaio-Ken, the humans wouldn't be that special. However Piccolo would be pretty powerful with it. Oob would be a monster. Cell should know the move since the spybot's showed off Kaio-Ken which Gero knows of.

The Genki-Dama is a pretty big gamble of attack as it leaves someone wide open. So it's not really that good of a move since in most cases it would be pretty useless. It'd only be useful if say Mr. Satan could do it or if Mr. Satan was around, otherwise the power needed for it probably wouldn't do it against powerful foes.

[ZazamPow]

As mentioned, King Kai himself couldn't even do the technique properly. Goku is the only character in the series shown to master the technique, and since Goku is by far the most skilled fighter, I think that tells us the other characters simply wouldn't be able to learn it. I think the only real problem is why Cell didn't use it, which is something I never even considered before. I don't think there's an explanation behind it though, it's just a plothole.

Also, even if Tien, Krillin, Yamcha etc learned it, they still wouldn't make any difference in a fight. Assuming the humans are even with the Saiyans' base forms, a SSJ multiplies battle power by 50x, whereas the Kaio-Ken cap is 20x, and SSJ was already obsolete in the Androids arc. The humans or whoever else uses it would need to already be MASSIVELY stronger than the Saiyans' base forms in order to be relevant, which wouldn't make sense.

[FoolsGil]

The Genki-Dama is a pretty big gamble of attack as it leaves someone wide open. So it's not really that good of a move since in most cases it would be pretty useless. It'd only be useful if say Mr. Satan could do it or if Mr. Satan was around, otherwise the power needed for it probably wouldn't do it against powerful foes.

You say it's not a good move, but it's used so often in media. And half the time the opponent doesn't know the Bomb is being charged at all. Have Goku and the Saiyans and Piccolo be the distraction for 10-15 minutes. The humans are already under the radar of practically everyone, the opponent wouldn't know the true danger until the Spirit Bomb is thrown.

As for Mark, he's not needed. Yeah he would be needed to gather the energy from all the humans on Earth, but The Spirit Bomb could be formed from the energy of the Sun, so he's a moot point.

[TheGmGoken]

The same case with the SSJ grades. No one wants to put their body through that much pain. I guess they could master it. However to master it. They still have to endure the pain until they master it.

[RandomGuy96]

I initially, like Herms, just thought that the "amplify" statement meant that everyone was using Kaio-ken x10 invisibly now (which, now that I think about it, would also go a bit towards making sense of certain other scenes, like the kiri readings, or Piccolo's seemingly improbable power jump). I don't think Piccolo's comment makes much sense if he's actually talking about how they suppress their battle powers. He wouldn't use "amplify" in that case. On the other hand, if he really was talking about Kaio-ken, you'd think that something somewhere would mention that Piccolo and co learned the Kaio-ken. It'd only take a single line of unambiguous dialogue.

Assuming that no one is supposed to know Kaio-ken, we can assume that it's because the others just couldn't learn it. Kaio INVENTED the technique and he couldn't master it. Only Goku got to learn it, probably because he threw a temper tantrum and the universe responded by just handing it to him. People have theorized that maybe you need a physically strong body to handle it. Like a saiyan body. I don't agree with this, because in context the Kaio-ken has never made a distinction between being physically strong and just powerful in terms of ki. For example, Goku says that his body became tough enough to handle KK x10 after he raised his battle power via spamming zenkais.

[Lord Beerus]

I honestly thought the rest of Z-Fighters didn't bother with the Kaioken techniques because:

A) It was hell on your body to use
B) It takes too long to learn
C) Even when you master the Kaioken, it still puts your body through hell.
D) There is limit you can reach.

[dbzfan7]

I don't see a reason how it can be so taxing on the body when at certain levels it Kaio-Ken noticeable. At 90,000 x2 and x3 pretty much feel like nothing to Goku. They don't strain nearly as bad as before. At 3,000,000 x10 is what Goku can do without straining himself. Now someone with a massively higher power level such as Piccolo later on should not have a problem using the technique since he's way stronger than Namek Goku. Cell is much much stronger and should logically know of the technique since the spy bot was around. Yet never uses it. He could have demolished Gohan as an SSJ2 if he used a x10 which didn't feel like much to a 3,000,000 power level Goku. Oob would be monstrous with Kaio-Ken with his high power. I only have the god ki stuff as a maybe though as perhaps it doesn't work with godly ki, though really it probably should work.

I can't see how someone much stronger than Namek Goku can't wield Kaio-Ken. Even teaching wise I don't see how none of them could learn that technique. If we go by DBO and Xenoverse, all races can use Kaio-Ken.

[Pantalones]

I figure the reason Cell doesn't use it is the same reason Goku no longer uses it--he has his own "Super Saiyan-like" state, which makes Kaio-ken obsolete. Unless "Super Kaio-ken" from the dead-people-tournament filler really is possible, anyway.

But yeah, Kaio-ken Piccolo would be absurdly powerful. Considering that he's already not that far off from Cell Games Vegeta and Trunks at that point in the series, he'd easily be able to pass the Saiyans and even Cell himself if he just powered up using a few levels of Kaio-ken, let alone x10 or x20! Considering that SSj3 isn't even a 10x boost over regular Super Saiyan, and Piccolo isn't that far beyond the regular Super Saiyans... Piccolo could easily surpass SSj3 Goku if he could use high-level Kaio-ken ontop of his Buu saga power.

And Buu if he could learn it, or Uub after reaching his potential, would be insane. Fat Buu Kaio-ken x20 vs. Kid Buu would be a really odd (...and anti-climactic, considering just how much stronger Fatty would be with that kind of boost!) alternate ending to the Buu saga.

I'm guessing Kaio-ken isn't quite compatible with godly ki, though--would help explain why the North Kaio could never use the technique he developed, since all of the gods should have at least some god ki even if their ki isn't 100% god ki like Beerus and Whis. And maybe Kaio-ken just stops working as efficiently once you pass a certain level of power? It works fine at 3,000,000, but maybe its effect starts to drop off rapidly once you start pushing upward into the tens of millions (like, say, maybe a Kaio-ken x20 at 30,000,000 is only as good of a boost as a Kaio-ken x4 or x5 would've been back in the single-digit millions), and becomes borderline useless at the hundreds-of-millions point (not even a full doubling of your power even if you tried to crank it up to Kaio-ken x100 or something crazy like that, at which point the strain hurts you more than the power boost can help, like SSj3 with a living body but worse.)

[Jackal puFF]

It probably took too much of a toll on the body. Just look at Goku using it against Vegeta and Frieza. Sure he was getting a bit of an upper hand on them but at the end he was worn and torn tired. Those were the times Goku got pretty beat up. I can imagine him sharing that to the others. Maybe Tien and Yamcha didn't wanna use it cause of their "pride". Doubt that but maybe.