The object of the game is to move the tiles on the board, until each row or column contains the same tile. The challenge is to do this with the least number of moves possible! The difficulty depends on the board size, which can be chosen between 4x4 tiles (piece of cake) and 10x10 tiles (very difficult).
In the Challenge Mode, you're challenged to complete a board within the maximum number of moves allowed. When you succeed, you get points awarded, and a new challenge. Challenges will keep getting harder, and you'll need to gain insight, and learn the tricks of the game, to complete them all!