The company is developing the title in-house and plans to release it on GREE for feature phones and smartphones in November (pre-registration started today).
Oozumou Card Kessen is licensed by the Japan Sumo Association, a first for a social game. As the name suggests, GREE decided to play it safe and went for the card battle genre.
In the game, users can build their own sumo stable, train wrestlers and have them fight wrestlers from other GREE players. Needless to say, Oozumou Card Kessen features real-life sumo stars.