Pokémon Colosseum was released on November 21, 2003 in Japan, March 22, 2004 in North America and May 14, 2004 in Europe on the Nintendo GameCube. The game followed the basic stadium style battling found in the Pokémon Stadium games but an extra was included in the form of an RPG which allowed trainers to catch Generation II and Generation III Pokémon in the desolate region of Orre.
In the game, the player character Wes was part of an organization called Team Snagem and they obtained a machine which allowed someone to snag another's Pokémon as if it were wild. Another team, Cipher, was responsible for corrupting the hearts of Pokémon and giving them to Trainers. With the help of a young girl named Rui, Wes was able to find the Pokémon whose hearts were sealed and surrounded by a purple aura and use the Snag Machine to rescue Shadow Pokémon and restore them to normal.