Full list of all 12 Tetris Splash achievements worth 200 gamerscore. It takes around 15-20 hours to unlock all of the achievements on Xbox 360.
Complete a Single Player game of Marathon in 20 minutes or less.
Accumulate at least ten hours of Online Multiplayer game play.
Complete a Single Player game of Marathon without using the Hold Queue.
Perform a Single, Double, Triple, Tetris, T-Spin Single, T-Spin Double, and 8 Combo in one game!
Clear one or more lines with successive pieces to increase your Combo count above eight.
Rotate the T-Tetrimino into a T-Slot to perform a one or two line clear.
Win a "Free for All" match in Online Multiplayer.
Score a Back-to-Back Tetris in Online Multiplayer.
Reach or exceed level five in a Single Player game of Marathon.
Clear five or more lines during one Single Player or Online Multiplayer game.
Clear four lines at once.
Use at least one Mino from each of the seven Tetriminos to clear a single line.