DUOtris is a take on Tetris (GB). Instead of blocks coming from the top, and fall down, blocks come from both top and bottom, and gravitate towards the middle.

The aim of the game is to get the highest score possible. Points are scored by moving the falling blocks on both sides of the play area so as to arrange 3 or more blocks of the same colour together. These blocks will then disappear causing any blocks "above" them to fall and possibly create further combinations. The game ends when either stack of blocks crosses the game over line. Over time the speed of the blocks increases, more colours are introduced and the play area becomes narrower.

There are two different game modes: Classic where there are just blocks falling, and Arcade where you get powerups and special blocks.