Things You'll Need
Instructions
Defeat the Elite Four. Completing this step is a vital precursor that will make Raikou available in your game.
Find a large patch of grass and walk in it until you encounter Raikou. There is no way to narrow down his location until your first encounter. After you've spotted him once, his image will appear on your regional map, making him easier to find.
Battle Raikou. Use status-impairing moves, such as sleep powder or thunder wave, to make him easier to catch.
Lower his HP until it is in the red zone and as close to zero as possible.
Use a master ball or ultra ball to catch Raikou. If you are using ultra balls, you will need 20 to 40 to catch him.