Start/End Dates	2013-01-31 through 2013-03-21
Country	United States

Details

League Players: Get your Garchomp!

A tough and battle-ready Garchomp is waiting for Pokémon League players!

If you are registered as having played at a Pokémon League event, you automatically qualify for this Garchomp. All you have to do to get this Pokémon is go to the Promotions page at the Pokémon Global Link and follow the instructions. The next time you use Game Sync, Garchomp will be added to your game!

Source: http://www.pokemon.com/us/pokemon-news/op_pgl_claim_garchomp-2013-01-31/