X-masBlox is a Tetris clone. The principle is the same: blocks of different shapes are falling down from the top of the screen. The player can turn and position them until they reach the ground - when that happens the next block (which is shown beforehand in the upper right corner) starts falling down. If the player constructs a continuous line of blocks they disappear and reward points.
Music and sound samples can be turned on or off. The only difference compared to the original is that shapes are Christmas-themed.