First of all read instruction of this game and also see controls of the game above.You will also find Instruction of the game on game page.You can acces the game by clicking here.
You only get three chances to undo your move in one game. There are 25 challenging levels to get through - all of them locked, save the first one. The first few levels are easy but it gets harder and harder at each level. Go back and try to earn the gold star in every level. Don't forget to submit your scores and check back to see who's beating you.