I'm assuming you mean King's Rock.
Icirrus City: Gift from chairman of the Pokémon Fan Club, if Pokémon shown has gained 99 levels since it was met in a Generation V game.
Route 13: From the Treasure Hunter. You have a 1/27 (3.7%) chance of getting a King's Rock
Pickup: If you walk around with a Pokemon with this ability between the levels of 11-30, you have a 1% chance of picking one up.
Held by the following Wild Pokemon: