Way back in Dragon Ball, we were introduced to Kami, the guardian of Earth. Kami's name essentially translates to a word meaning deity or god. Thus, Goku essentially trained with with a god. But, as Dragon Ball Z rolled on, we learned that Kami wasn't the highest deity out there. Goku trained with yet another deity, King Kai, the Kai of the north quadrant of the universe. But it doesn't stop there, and we'd eventually be introduced to the lord of lords, the Grand Supreme Kai that acts as ruler of the universe. That's not even the end of it either, since all the Grand Supreme Kai report to Zen-Oh, the king of everything, all the universes and the Kais who govern them.
The world of Dragon Ball is full of insane elements, and the Kais are some of the crazies and coolest of them all. The Kais are not only powerful, possessing powers that mortals do not, but they are also wise lords, governors of life and death, and great teachers to boot. Goku and the gang have met, saved, made friends with and trained with a few different Kais over time, as well as fought against them, so here are a few facts about the strange and eccentric deities of Dragon Ball.
The hierarchy of the gods starts with the planetary guardians, those like Kami and Dende that watch over a single planet and are not born into their position. The guardians report to the kai of the district that their planet is in. In the case of Kami, he reports to King Kai, the Kai of the north.
There are three other Kai, one for each quadrant of the universe. These Kais report to the Grand Kai, who in turn reports to the Supreme Kai. There are four Supreme Kai (though, this depends on the universe), and one Grand Supreme Kai. The Grand Supreme Kai works in tandem with the God of Destruction (a mortal that is given this job and becomes a god as a result), as the highest authorities of their universe. But, it doesn't stop there either, as these two report to Zen-Oh, the king of all universes.
15 KING OF THE NORTH
No, that's not a Game of Thrones reference, it's actually King Kai's job description. See, King Kai is the Kai of the north quadrant of the universe and as such is otherwise known as the North Kai. Though the South Kai is the only other Kai to make a canonical appearance (the others only appearing in filler), this still means that King Kai is the only one who goes by a different name.
What is the reason for this exactly? Well, it's never actually stated. Perhaps it's because Akira Toriyama didn't originally plan on creating gods beyond King Kai himself, but who's to say. What we do know is that King Kai has still been referred to as the North Kai by several characters, so he voluntarily goes by a name that makes him seem better than the others. Talk about ego!
14 THE KAI OF TIME
There was one Kai that we left out of the entire hierarchy, the Kai of time, Chronoa. Chronoa was given the position of the Supreme Kai of Time after raising Tokitoki, a time bird, into adulthood. As the guardian of time, Chronoa watches over time and stops any rifts from occurring that could disrupt the flow of time. It is also partially Chronoa's duty to make sure that no rogue timelines are created, and all these duties are fulfilled with the help of the player in the Dragon Ball Xenoverse games.
Chronoa is not featured in Dragon Ball outside of videos games and thus her place in the canon is sort of up in the air. That said, it's interesting to think that there is a god of time that is essentially there to keep the already complicated organization of the governing of mortals from getting more complicated.
13 THE GRAND KAI
Some might think that, like Chronoa, the Grand Kai's place in the canon is sort of vague. But, this is actually incorrect. Though the Grand Kai's only appearance was in a filler arc of Dragon Ball Z, he is still mentioned in the Dragon Ball Z manga. Further evidence of his place in the canon is the fact that Akira Toriyama came up with the design for the Grand Kai that was used in the filler arc.
The Grand Kai stands above the other Kai as their leader and supposedly reports to the Supreme Kai. He is not the ruler of the universe, but instead the ruler of the lower Kais. He acts as an overseer to the other Kais and perhaps as some middleman between the Kais and the Supreme Kais.
12 KAI BY DEFAULT
The hierarchy of the Supreme Kai is a bit confusing at times. There's no set number of Supreme Kai that can exist at once and not all of them actually rule at the same time. However, in Universe 7, there is only one Supreme Kai left... sort of. Shin is the current Grand Supreme Kai of Universe 7, and he got that position when every other Supreme Kai in his universe, including the former Grand Supreme Kai, were killed by Buu.
Shin is the only Supreme Kai left and thus he is, by default, the Grand Supreme Kai of Universe 7. However, there is one other Supreme Kai, the Old Kai that was sealed in the Z-Sword. There's never really a reason given for why Shin's position as Grand Supreme Kai isn't relinquished back to the Kai who held the position before him, perhaps because his time has passed.
11 GODS OF CREATION
In Dragon Ball Z, the Supreme Kai were referred to as just that: the Supreme Kai. However, with the introduction of the Gods of Destruction into the canon, the Supreme Kai were said to be the opposites of the Destroyers as the Gods of Creation. As the Gods of Creation, the Supreme Kai provide the catalyst for new life in the universe they govern.
The Grand Supreme Kai stand above the other Supreme Kai as leaders, but all Supreme Kai have the ability to create life in the universe. This also tells us that the Grand Supreme Kai are not just overseers or managers of their universe, like the Grand Kai, but instead have an active role in their universe, providing the catalyst for new mortal life.
10 THE KAI RACE
This is perhaps the most interesting, and least known fact of them all. All Kai, both lower and Supreme, are of the same race. They are known as the Shinjin and how they come into being gods of the universe is pretty cool. They are all born from the Kaiju, magical trees that only grow on the Kaishin, the planet of the Kais.
The Shinjin sprout from the fruit of the Kaiju and are born with power far greater than that of an untrained mortal. They possess godly ki and some are chosen to be Kai. Those that are born of golden Kaiju fruit are destined to be Supreme Kai, though there are some exceptions. All Shinjin also share some traits in common, like a humanoid appearance and pointed ears.
9 KAI CAN DIE
Another thing about the Shinjin is that they are some of the only living residents of Otherworld. Otherworld is the afterlife of Dragon Ball and exists as some sort of parallel dimension to the universe. It is mostly inhabited by the souls of the dead, but the Kai also reside in Otherworld, governing the universe from the afterlife.
However, this does not mean that Kai cannot die. They might live for a long time but they can still be killed. This was seen when King Kai was killed by Cell, who was transported to King Kai's planet by Goku just as the villain was about to self-destruct. The Old Kai also showed that Kai can have halos when he gave up his life to return Goku to the world of the living.
8 LIFE LINKS
Speaking of life and death, if the Grand Supreme Kai dies, then so does the god of destruction. This is because of the life link the two share. The Supreme Kai are the gods of creation, the opposite of the Gods of Destruction. The two are meant to work in tandem with the balance of the universe, the God of Destruction work to rid the universe of threats to mortal life and the Supreme Kai work to create new life in place of the destruction.
To ensure that they work together, their lives are linked, meaning if one is killed, the other dies with them. Both are gifted with longevity, living thousands of years, but they are not immortal and can be killed by anyone stronger than them, meaning that threatening the life of one also threatens the life of the other.
7 GODLY PROMOTIONS
As previously stated, nearly every Supreme Kai was born into the position. The Shinjin that are born of golden Kaiju fruit are destined to be Supreme Kai, but there is another way to gain the position of the God of Creation of a universe. In Dragon Ball Super we meet Gowasu, the Grand Supreme Kai of Universe 10. Gowasu is training an apprentice to take over from him, Zamasu.
Before Gowasu took him under his wing, Zamasu was just a simple Kai, the North Kai of Universe 10. Zamasu was promoted and was being groomed and trained by Gowasu to take over for him as Grand Supreme Kai. However, that all changed when his zero-mortals plan was revealed and he was erased from existence by Beerus.
6 MORTALS VS KAIS
Between the Supreme Kai and the Gods of Destruction, the Supreme Kai are much weaker, even the Grand Supreme Kai. That said, they're still incredibly powerful, capable of defeating Frieza prior to his training in Dragon Ball Super, at least according to them. However, this doesn't mean that they are more powerful than every mortal, in fact, it's made clear that most Saiyans have surpassed their power levels.
But, it's not just Saiyans, there are a few mortals that are far more powerful that all the Kais. A good chunk of the fighters in the Tournament of Power are most likely stronger than their Supreme Kais, a fact that is definitely true of Jiren the Gray. Jiren is so powerful in fact, that he may have very well surpassed the Gods of Destruction.
5 KAI PLANETS
There are quite a few worlds tied to all the Kais. The planet they originate from is the Kaishin, where the Kaiju tree grow. When a Shinjin is born from the fruit of this tree, some are assigned to be a Kai of a quadrant of the universe. This position comes with a planet to call their own located at cornerstones of the four quadrants of Otherworld, allowing them to look over their areas of the universe.
There is also the sacred world of the Kai, a planet located outside the universe. The sacred world of the Kai exists separately from the universe and is where the Supreme Kai live, including the Grand Supreme Kai. This planet is also used as a meeting place between Grand Supreme Kai and Destroyer Gods at times.
4 GODLY KI
This one probably doesn't surprise anybody, since the Kais are gods after all. Regardless, every Kai from the lowers to the Grand Supreme possess godly ki, a ki different to the energy of mortals that is much stronger in nature and gives the kai special abilities and increased power.
Godly ki is actually something that was retconned into the world of Dragon Ball as it wasn't mentioned until Battle of Gods and the Dragon Ball Super adaptation of the story. When the Z-fighters could not sense Beerus' energy, it was revealed that only those who have access to Godly Ki can sense it, with some exceptions. However, Shin and King Kai's power were able to be sensed by mortals in Dragon Ball Z, adding to one of Dragon Ball's many (sometimes beloved) inconsistencies.
3 THE KAI KAI TECHNIQUE
When Instant Transmission was introduced into Dragon Ball Z, it was one of the coolest techniques that Goku had learned. However, it has its limits. Goku has to lock onto someone's energy, he has to be able to detect it in the first place and it can't work over a certain distance. There is, however, a technique more powerful than Instant Transmission, the Kai Kai technique.
This is a technique that only the Supreme Kais can use, but there are a few exceptions. Kibito is not a Supreme Kai but he is able to use it and Kid Buu managed to somehow master it. The Kai Kai technique allows Supreme Kais to teleport anywhere they can think of with no limits on distance and no need to lock on to energy.
2 POTARA FUSION
The Supreme Kai are never seen without their signature Potara. These earrings are not only the mark of a Supreme Kai, they are also a powerful tool. See, there are various types of fusion in the world of Dragon Ball, one of the most powerful being Potara fusion. When two warriors wear one of the earrings on the opposite ears, they will fuse into a warrior far more powerful than the sum of their parts.
What does this have to do with the Supreme Kais? Well for one thing, they are the holders of the Potara earrings, which also give them access to the time rings. Secondly, when two Supreme Kai fuse, it is permanent. This was thought to be the case for all who use the Potara, but it turns out it's just for Supreme Kai, and it took a wish from the dragon balls to unfuse Kibito and Shin.
1 GODLY ATTENDANTS
Akira Toriyama has an interesting way of writing deities, a very present element in the world of Dragon Ball. He likes to think of them as officials that require an attendant or bodyguard, similar to a person in a political position of power. This is most likely the reason for various gods in the series having personal attendants.
Kami obviously has Mr. Popo, Beerus has Whis and in the case of the Supreme Kai, there are two known to have personal attendants. The first is Shin, who is guarded by and attended to by Kibito, who he eventually fuses with. There is also an unnamed attendant, the one who serves Fuwa, the Supreme Kai of universe 6, though we doubt those two have ever been fused with each other.