With the 9 x 9 grid, this number puzzle is the biggest challenge from the Rubik's Cube. The empty cells must be filled in so that the numbers from 1 to 9 appear only once in each row, each column, and each 3 x 3 block. And the best part is that you don't need to be a number enthusiast or a math genius to love Sudoku.

Includes 5 levels of difficulty. This...