Mixing the strategy of Rampart and the puzzle elements of Tetris, Fortress will have players using blocks to build forts around four themes: caveman, medieval, pirate, and futuristic. The reason for building your fort, of course, is that an opponent (either the computer or up to three friends networked to your GBA via the separately sold communication cable) is trying to knock you silly with projectile weapons. The better you are at building smart fortification, the better you'll be able to return your opponent's volleys. Also, special magic spells and attack soldiers add depth to the game.