In crystal version the most common places to find Entei?

Entei is a Legendary Pokémon, and as such, it doesn't have a set location in the wild in Pokémon Crystal. You can only obtain Entei in the following ways:

* Via Event: Entei was originally distributed as an event Pokémon in Japan, and it has also been distributed as an event Pokémon in other regions at various times. This is the only way to obtain Entei in the original Crystal game.

* Trading: If someone else obtained Entei through an event or possesses a cloned copy, you can trade for it.

* Game Shark or Action Replay: These devices can be used to insert the Pokémon into your game, but this is considered cheating by many players.

It's important to note: Entei is not available through normal gameplay in the original Pokémon Crystal.