Here are thousands of free Sudoku puzzles to print. Each booklet of printable Sudoku contains eight puzzles, instructions, hints and answers. If you like these. Jigsaw Sudokus (also known as Irregular, Nonomino, or Geometric Sudoku) are very similar to regular Sudoku puzzles, but instead of 3x3 blocks, they are Challenging Jigsaw Sudoku · Super-Tough Jigsaw Sudoku · Tough. backg.review numbers in each group (surrounded by thick lines) must not repeat. Instructions: Category: Sudoku Puzzles. Note: This game requires Adobe Flash Player.