Classic Sudoku Game. Click on a cell to enter a number. You can enter numbers from 1..9. Every number can only occur once per row, column and 9x9 box. To delete a number using the numeric keypad in the game, you must enter the number again.
Remove all cards from the Tower. You can remove cards from it when the card is 1 higher or lower in value than the open card (top left). Click on the closed stack to get a new open card.