❶Each row must contain all of the numbers 1 through 9 and no two numbers in the same row of a Sudoku puzzle can be the same.
❷Each column must contain all of the numbers 1 through 9 and no two numbers in the same column of a Sudoku puzzle can be the same.
❸Each block must contain all of the numbers 1 through 9 and no two numbers in the same block of a Sudoku puzzle can be the same.
Select a cell from the 25x25 puzzle, and enter a number using the number keypad or the memo number keypad.
By double-clicking on a cell, you can keep entering the same number you chose on the keypad. You can erase a number by entering that same number.
C: Clear the cell
UNDO: Go back one move
RESTART: Reset the puzzle
CHECK: Tells you if you have made a mistake
HINT: Shows you the next move
POSSIBLE CHOICES: Automatically sets the possible choices.