The answer you are looking for is radjabov.
What players where/are really good at the King's Indian defense?

I recall in a Sam Shankland lecture he referred to the KID at the GM level by comparing it to something like the Lativan Gambit, objectively unsound at the top level but most players don't know how to punish it. That really surprised me because I (and most people) considered the KID to be one of the most theoretically sound openings.

Eduard Gufeld. Read the Art of the Kings Indian by Eduard Gufeld. the games are dated from the 50s and the 60s. But in my opinion, he shows the basic plan that you need to understand as black in a majority of variations.

King's Indian is all based on the fact that who is faster. If white manages to slow down black,then he's winning. That's the mantra to win with the king's Indian that is,be the fastest one.

rupam44, I agree. the best example is the Bayonet attack with b4 in the classical line. but I might also would add the fastest, the bestest, and the mostest. Black needs all his pieces in the king side attack. the thorn in blacks side is how will he handle Bg5 by white. which completely changes all his normal ideas.
I usually pre-move Nf6 for my first move to not waste any time in any time format. A lot of people play e4 first so I move into the Alekhine, which I have lots of experience in, but sometimes they play d4 first and I thought it would be interesting and useful to know the King's Indian defense as well. I think to start studying I would need some players that are really good at it that I can study. Please and thank you.