A 3x3 grid of tiles is manipulated by rotating 2x2 squares within it. The object is to arrange the tiles into a given pattern. Within the 3x3 grid, there are four 2x2 squares within it that you can rotate: the four tiles in the upper left, the four tiles in the upper right, the four tiles in the lower left, and the four tiles in the lower right. You can rotate these 2x2 squares either clockwise or counterclockwise. Source: The Game Website.