Sudoku

The basic rules of Sudoku are easy. Just place the digits from 1 to 9 in each empty cell. Each row, column, and 3 x 3 box must contain only one of each of the 9 digits.

Solving these puzzles is a different matter entirely, since these are the most difficult puzzles we create. Difficulty depends on the type of steps required to solve them, and also on the number of each type of step.