A King's Rock is an item introduced in Generation II that allows Poliwhirl to evolve into Politoed and causes Slowpoke to evolve into Slowking when traded. This item also raises chance of causing opponents to flinch by 11.7% with most attacks without any secondary effects.
- Pokémon HeartGold and SoulSilver, Crystal, Gold and Silver Version: It can be found in Slowpoke Well.
- Pokémon FireRed and LeafGreen Version: It can be found in Sevault Canyon.
- Pokémon Platinum Version : It is hidden inside Celestic Town.
- Pokémon Black and White Version (2): After you show a Pokémon you raise from level 1 to level 100 to the Chairman of the Pokémon Fan Club in Icirrus City, he will give you one of this. In Version 2 another one can also be found in Nuvema Town.
- Pokémon X and Y: After Clemont is defeated, Lysandre will offer you one of this at Lysandre café.
- Omega Ruby and Alpha Sapphire: It can be found in Mossdeep City.