From left to right: South Supreme Kai, North Supreme Kai, East Supreme Kai, West Supreme Kai, The Grand Supreme Kai.
I know these characters have very little showing and this battle would be difficult to discuss properly but i wanted to try it anyway so here goes.
South Supreme Kai has the most showings and screentime from all the other Kai's with the exeption of East Supreme Kai ofcourse. When he and Kid Buu fought at the start of there battle they seemed to be evenly matched, South Supreme Kai was fast enough to dodge some of Kid Buu's energy attacks and punches and even manages to rip one of Kid Buu's arm of by sheer brute strenght. Later on Kid Buu dominated the battle eating one of South Supreme Kai's energy attacks (literally) and kicking South Supreme Kai in the neck doing severe damage and eventually absorbing him. Now to me it looks like South Supreme Kai could be around SSJ2 lvl as he managed to give Kid Buu some actual trouble in there fight. He could be as strong as Vegeta SSJ2 maybe a little stronger, Vegeta however showed a greater durability than South Supreme Kai and did a little more damage to Kid Buu than South Supreme Kai did.
North Supreme Kai had the least amount of showing, you only see him charging Kid Buu with his sword cutting him in half and later dies by one of Kid Buu's energy attacks. My wild guess is that he is a very weak SSJ opponent maybe somewhere around Android 17/18 lvl.
East Supreme Kai had only a brief battle with Fat Buu in the show, he did pull some interesting attacks but proved inefective against Fat Buu wich is weaker than Kid Buu. East Supreme Kai is also very afraid of Dabura and doesn't want to cross his path, so it shows that the East Supreme Kai isn't a very powerfull opponent as Dabura is easily an SSJ2 lvl. East Supreme Kai to me looks he might be a little more powerfull than North Supreme Kai but not by a hugh amount, maybe around Android 16. The fusion with Kibito, making him Kibito Kai, should increase his power by a good deal perhaps matching Semi Perfect Cell.
West Supreme Kai was the first Kai Kid Buu fought, she hasn't had the best showing either, you see her getting pummel'd by Kid Buu, she briefly manages to deal some punches but then is thrown against an ice wall. She then fires an energy attack at Kid Buu but Kid Buu kicked it away and then he finishes her of. West Supreme Kai showed a bit more resistence than North Kai or even East Supreme Kai but not by a whole lot so i think her powerlvl isn't far from East Supreme Kai.
The Grand Supreme Kai is an interesting one, altough he also had little showing he displayed alot of power against an stronger Majin Buu namely Bulky Buu or Mega Buu or whatever people call him, the one when he absorbed South Supreme Kai the very big on :). The Grand Supreme Kai deflected Mega Buu's energy attack with an energy field similair that of Mystic Gohan when he was fighting Buutenks, deflecting the attack back at the opponent. He then fires an devestating attack that cuts Mega Buu into pieces and it didn't look that he wasn't straining himself either. Its clear that in order to deflect such an attack in the way he did you'd need alot of power, it does not mean he's stronger than Mega Buu but at the least should be in the same league like Mystic Gohan did against Buutenks, so either The Grand Kai is around SSJ3 or around Super Buu (maybe weaker)
Its worth mentioning that the East Supreme Kai has mention'd before that each Kai is far more powerfull than Frieza so thats why i put North Supreme Kai around Android lvl and not stronger because, East Supreme Kai did not know about Cell or the Androids. When East Supreme Kai was talking with Goku about Dabura's powerlvl Goku replied: *Yeah Dabura is strong but he's not unbeatable, about 7 years ago we fought a guy named Cell now he was tough.* and its pretty clear by anyone that the East Supreme Kai overlooks alot of things....alot....of things.
Keep in mind these are all my opinions and if you think i'm wrong about any of there powerlvls, maybe you think there far stronger or even weaker, feel free to correct me, like i said they have little showing so this would be difficult. Now for the actual battle!
- Location Supreme Kai World
- No Morals
- No prep
- No Planet Busting
- These are all Team Battles
- East Supreme Kai is Fused with Kibito, thus - Kibito Kai
Round 1: Frieza (100%), Cooler (Final Form), King Cold, Lord Chilling, Bardock SSJ
Round 2: Android 18, Android 17, Android 16, Super Android 13, Imperfect Cell (Full Power)
Round 3: Super Vegeta, Super Trunks, Teen Gohan SSJ, Piccolo (End DBZ), Goku SSJ (End Cell Games, the same for Trunks/Gohan/Vegeta)
Round 4: Olibu, Pikkon, Bojack (Final Form), Perfect Cell (Full Power), Hatchijack (Final Form)
Round 5: Super Perfect Cell, Dabura (No Spit), Adult Gohan SSJ2, Vegeta SSJ2, Goku SSJ2 (Start Buu Saga, same for Vegeta,Goku has the same powerlvl as Majin Vegeta)
Could the DBZ Gods clear this gauntlet or will they fail.
EDIT: After some thinking i believe that the Kai's are stronger than i originally thought. For example: i said that East Supreme Kai could be as strong as Android 16 but if that where the case he could not hope to hurt Fat Buu in there battle as East Supreme Kai did in fact fire'd an energy attack at Buu blasting him away, or West Supreme Kai couldn't have lasted that long against Kid Buu if her power was around the Androids, seeing as Semi Perfect Cell blasted Android 16 away with one energy attack. I think there powerlvl could be around Goku's when he fought against Cell or maybe and its a big maybe, rivaling Perfect Cell in Full Power (NOT Super Perfect Cell)
EDIT 2: I rewatched the episode for the second time, the battle between South Supreme Kai and Kid Buu: I made a comment that i thought South Supreme Kai should not be stronger than Vegeta SSJ2 because South Supreme Kai had poor durability (every Kai for that matter), but that could also easily be, and probably is, is that these battles needed to be resolve quickly to advance the story, South Supreme Kai was actually already fighting Kid Buu before the flashback started, so they where fighting alot longer than i originally thought, and i also forgot that South Supreme Kai tanked a charged headbutt from Kid Buu the SAME move Kid Buu used against Vegeta witch knocked him down, so that means South Supreme Kai should be alot stronger than Vegeta SSJ2. I would say that Majin Vegeta, Goku SSJ2 and South Supreme Kai are pretty much even in terms of power.
EDIT3: After a fun debate with SpeedForceSpider i've come to a dissision about some of the Kai's powerlvl's, note this is my opinion:
I say Grand Supreme Kai could be around SSJ3, maybe an low/mid tier one or perhaps just as strong, still not completly sure about him. South Supreme Kai should be stronger than Vegeta SSJ2 but not Majin Vegeta or Goku SSJ2, SpeedForceSpider thinks Vegeta SSJ2 is still stronger. North and West could be around Goku SSJ at the time around the Cell Games, SpeedForceSpider thinks there around Super Vegeta. Kibito Kai should be high tier SSJ and maybe a low tier SSJ2 at best.