The book contains 200 excellent Jigsaw Sudoku puzzles 9x9. Medium puzzles 100 Hard puzzles 100 All riddles have only 1 solution. 2 puzzles per page. The font size is correct you will not have to strain your eyes when solving puzzles. High quality paper and print (all puzzles read well, easy to write with pen and pencil without worry of bleed-through). Jigsaw Sudoku has irregular shaped blocks as opposed to the 3x3 square blocks in a regular Sudoku puzzle. Your task is to fill each row, column and irregular shape with the numbers 1 - 9, no number may appear twice in any row or column and irregular shape.