It was announced in the January 2008 issue of CoroCoro and was released in Japan on March 20, 2008. It was announced at E3 2008 that the game would be released in the United States under the title Shadows of Almia on November 10, 2008. It was announced on September 25 that the game would be released in Europe under the title Shadows of Almia on November 21, 2008.
The game features 270 Pokémon, including new Pokémon which were not featured in the original Pokémon Ranger, from Pokémon Diamond and Pearl. The game utilizes the Nintendo Wi-Fi Connection to download new missions.