Kaioken explained: why is Goku the only one who uses it?

The Kaioken is one of Goku's most iconic techniques, and I'd argue it's almost a representation of the pre Super Saiyan era of Dragon Ball Z. Does an image of Goku using it not bring back warm, nostalgic memories of the early parts of Dragon Ball Z, whether you saw it on Cartoon Network, in syndication or anywhere else? It came back later on as well. But what is the Kaioken, how does it work, and where did the idea come from? Here is my detailed look at the technique.

What the name Kaioken means and why it belongs to King Kai

The Kaioken is the technique invented by King Kai, known as Kaiosama. It's his technique, which is why it carries his name. The original Dragon Ball Z dub mispronounced it as "Kao ken." Later dubs, including Dragon Ball Super and Kai, fixed that problem.

An easy way to translate Kaiosama, the name rendered as King Kai or Lord Kai, is the lord of the worlds. So the move would translate to lord of the worlds fist. The Toei subtitles for Dragon Ball Super call it the King Kai fist. That's a decent translation, but his name isn't really King Kai. Either way, Kaioken is a perfectly good way of describing it: lord of the worlds fist, or fist of the world king, whichever you think is cooler. Or just call it Kaioken, which most of us do.

One thing Dragon Ball Super has taught us is that the gods all have unique and strange abilities that mortals have never heard of, and the Kaioken is one of them. Nobody used the Kaioken until Goku met Kaiosama at the end of Snake Way, trained with him and learned to master the move.

Goku is the only character we've seen use the Kaioken

The Kaiosama we know is the North Kai, but there are three other Kais as well. Do any of them know the Kaioken? The world may never know.

Another question I often hear is whether Goku's friends, like Piccolo and Yamcha, who also trained with King Kai during the Frieza Saga, know the technique. Some of the games may lead you to believe that they do, but we've never seen these characters use the Kaioken. The only person we've seen use this move is Goku. I'm not including games or Heroes here. It's Goku's move.

Goku learned two techniques from his training with King Kai that would become signatures in his arsenal: the Spirit Bomb, or Genki Dama, and the Kaioken.

Some people will bring up Chi-Chi doing the Kaioken in the Garlic Jr. Saga. That's a gag scene. It's supposed to be a funny moment, it's not really the Kaioken, and it's not in the manga either.

Goku's first Kaioken against Nappa in Dragon Ball Z episode 29

We don't see a visual representation of the Kaioken until Dragon Ball Z episode 29, which corresponds with Dragon Ball manga chapter 226. In this epic scene, Nappa is about to attack Krillin and Gohan. Goku screams Kaioken, is surrounded by an awesome looking red aura, propels through the sky and double punches Nappa in the spine, finishing him with one burst of power.

Nappa was so hurt by this technique that he couldn't even move. He was paralyzed shortly after. That's how much pain Goku inflicted on him with the Kaioken.

Kaioken multipliers and the hidden Kaioken against Frieza

As Goku evolved in his training, he learned to tap into Kaioken multipliers: times two, times three, times four, later times ten and times twenty, and even times one hundred in one of the Dragon Ball Z movies.

What's interesting is that as Goku normalized the technique with his body through training, he also learned to mask its visual representation. During the fight with Frieza, Goku's friends wonder why he isn't using the Kaioken. Kaiosama reveals that he was using it the entire time; they just couldn't see it. This horrified Goku's friends, because they thought he might have had a chance against Frieza with the Kaioken, and the reality is he didn't.

When it comes to the Kaioken, the Frieza Saga is more or less the last time it was truly relevant. We don't really see it in the Cell Saga or the Buu Saga. We did see it in the Other World Tournament filler arc, which is anime only, and in some of the Dragon Ball Z movies even after the Frieza Saga. It made a grand return in Dragon Ball Super. For the most part, though, the Kaioken was phased out for much of the latter part of Dragon Ball Z.

What the Dragon Ball guidebooks say about Kaioken limits

Most of Goku's training on King Kai's planet happened off screen, so we never saw how he was taught the technique. To understand how it works, we have to look beyond the manga, which is often necessary with these techniques. That means reading the Dragon Ball guidebooks, and also material outside Dragon Ball that may have influenced it.

The guidebooks describe it as "a technique that instantly amplifies the ki inside one's body multiplying all that person's abilities including power speed defense etc." They say it is extraordinarily effective in battles with formidable opponents, but because it is impossible to multiply excessively far beyond one's abilities, experimenting with an unreasonably high Kaioken might destroy one's own body. When the user's battle power is 8,000, their limit is times two; at three million, the limit is times ten. Since real battles are harsh, Goku often had to go above those limits. The guidebooks name the Northern Kai as the designer, but Goku was the first person able to master it.

King Kai even tells Goku not to go beyond times two. Unfortunately, Vegeta was too much for Goku to handle without pushing it, so he had no choice.

There's also an inconsistency between the Kaioken and Kaioken times two, because they appear to have the same multiplier of two. So would times two give you times three? It's very confusing. To me, the base Kaioken is an amplification, and times two is the actual multiplier. That makes the most sense: you amplify yourself with the Kaioken, then times two doubles that amplification, and so on as you reach higher levels.

Why Captain Ginyu couldn't use the Kaioken in Goku's body

When Captain Ginyu took over Goku's body, he couldn't tap into the Kaioken. The reason is the true explanation of how the technique works: the Kaioken isn't only physical, it's also a mental and spiritual technique. Using it properly requires an integration of mind and body.

Goku has to temper his mind and his body simultaneously. If his body isn't properly trained to handle the Kaioken, it will fall apart. If his mind can't tap into it, he can never use it. He could scream Kaioken all day and it wouldn't work.

Since the start of Dragon Ball, Goku has undergone rigorous training, so by the Vegeta Saga his body had been training his whole life, and learning the Kaioken wasn't too difficult. After the fight with Vegeta, he figured he needed higher multipliers, so he had to train his body again. That's why he trains nonstop in the spaceship on the way to Namek. The principles are similar to real world training: intense physical strain, repetition, integrating body and mind, and building endurance. That includes learning to take damage, not necessarily in combat, but from the Kaioken itself. Goku has to train the particles in his body to withstand its power.

How the Kaioken works from a Taoist perspective

Before turning it on, Goku taps into a deep form of ki inside his body until all of his cells become tight and filled with energy. That energy is then ignited, and that's how the Kaioken turns on.

A Taoist perspective, which is where many Dragon Ball techniques come from, offers more. The energy is drawn from the dantian, an energy field in the lower body, and sent out to the chest, the back, the head and the four limbs. The ki travels underneath the skin, causing the muscles to bulge and the flesh to thicken around the bones and muscles, preparing the body to withstand high amounts of energy.

There's no actual flame, but it's similar to one, because you're raising your body's temperature tremendously, even though it doesn't burn you or anyone else. As the energy reaches Goku's skin, it gives off heat, wind and electric energy that ignites. All of his cells open up, and his molecules, atoms and subatomic particles are tapped for a very brief time so he can deliver the strongest blows possible. Because of this, cells in his body die and take time to be replaced. That's why Goku steams afterward and needs rest: it tears him up every time he uses it.

Much of this information was provided by Derek Padula of The Dao of Dragon Ball.

Tibetan monks and the likely inspiration for the Kaioken

It's pretty clear to me that Toriyama got his idea from that Taoist concept, or possibly from Tibetan monks' fire, where monks can effectively set themselves on fire and not feel pain. I think the Kaioken was based on that concept, and much of it has to do with mental and physical training and making sure mind and body are one. In 1981, a Harvard Medical School researcher discovered that Tibetan monks can increase their body temperature by up to 17 degrees using a meditation technique called forceful breath. So the Kaioken is the Dragon Ball version of forceful breath, multiplied many times over.

I also believe the Kaioken was tailor made for a Saiyan, because of Saiyan genetics, their incredible endurance and their ability to keep fighting again and again. That lets Goku persevere rather than explode from using it at a high rate. That could be another reason his friends don't use it: their bodies may not be able to adapt to it like a Saiyan's. His gene pool and a lifetime of battle are what make the Kaioken one of Goku's signature moves, and why it makes sense that he can use it more effectively than others.