You have to fill in a 3x3 square with the numbers 1 through 9 so that the rows, columns and diagonals add up to specified numbers. Your score decreases with the time it takes to solve the puzzle. You are given the choice of buying a number at a cost of loosing time. This is fully functional as is but the shareware fee allows for saving scores and unlocks an expert version of the game. 35-second delay. You cannot record scores.