You do not control the movement of the square. It moves at a constant velocity, and switches direction upon contact with a wall. The features a dual coloured square, a purple map, alongside red and blue walls. The aim of the game is to toggle the colour of the square, which in turn also toggles which walls are visible. For example, when the square is blue, the blue walls are visible, and vice versa. You must toggle these to reach all of the fangolds. The game also features unlockable walls, where you have to collect hollow yellow squares to unlock them.