The player takes control of a character named Matt. The game is set in the future and the world is primarily surrounded by water. The only small patch of land called is called Terra. The player must show their worth to be accepted on to Terra by proving their skill as a submarine commander and destroying enemy vessels.
Matt's version features different characters, items and boats to Becky's version. These are logged in a device similar to a Pokédex. The battles take place against other ships. A radar view is used to help players guide torpedoes against the enemy. A large part of the game is text based with animated cutscenes. Two players can link-up with the cable to battle, exchange ships and accumulate other data.