He is deep inside of Mt.Mortar. You will need all 8 badges, as well as the HMs for Surf, Waterfall, and Strength to reach him. He is very far in, so it will take some time, and you may want to bring some Repels with you to conserve your Pokemon's strength to battle him, as he is a fairly strong trainer.
in that cave (not union ) in i think b2f
Mt. Mortar
In Pokemon Gold, Silver, Crystal, Heartgold, and Soulsilver the Karate King is in Mt. Mortar, East of Ekruteak City. He will have a Hitmonlee and Hitmonchan, and give a Tyrogue upon defeat if you accept it and have a space empty.
The Karate King can be found in Mt.Mortar in Pokemon Gold. You will need the HM moves Surf and Waterfall to reach the part of the cave where the Karate King is training.
If you have battled him he will give you a tyroge then nothing more happens
Normally, you would battle him. He has a Hitmonlee and Hitmonchan, and will give away a Tyrogue upon defeat.
Karate King in Mt. Mortar.
dodo
He is the Gym Leader in Cinawood.
The Karate King is in the basement of Mt. Mortar, East of Ekruteak in Gold, Silver, Crystal, Heartgold, and Soulsilver. He has a Hitmonlee and Hitmonchan, and will give away a Tyrogue upon defeat.
The Karate King! You can get a Tyrongue if you defeat him.
He is in Mt. Motar
he does not give you a gym badge, but you fight him at the end of Mt. ortar, rock climb is required. hope that helps...