Pokemon XD: Gale of Darkness

Is a video game for the gamecube. The story begins 5 years after the events of Pokémon Colosseum with the introduction of Michael (player may change the name), the main protagonist. Michael first meets Professor Krane, his mother's boss. He introduces the concept of Shadow Pokémon, which are Pokémon whose hearts have been artificially closed. So in the game you have to purify all the pokemon.