Game:

Pokémon HeartGold and SoulSilver (2009)

Duration: 4:51

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Both Raikou and Entei are roaming Pokemon.
To encounter them you must be in the same route as they are.
Since they teleport somewhere else every time you enter a new route, you have to pick ANY route and go back and forth.

Check your PokeGear to see if they teleported in the same route as you.
If they are go into some grass and make sure you use some repel.
You know when you encounter it because the music will change.

Raikou & Entei will try to run away on the first turn.
So use one of these moves to prevent them from running away:
Mean Look
Block
Spider Web
Also some Pokemon with abilities and moves can prevent escape too.

Make sure you have about 20 ULTRA or FAST Balls.

If one of them uses ROAR you will have to find it again.
There is no way to stop this from happening.
The Pokemon will not recover in the next encounter(s).

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