This Sudoku book is packed with the following features: 500 Hard Sudoku Puzzles Large print font for prevention of eye-strain All Solutions How-to-play instructions Are you an expert Sudoku puzzle player? Do you finish the average Sudoku puzzle in no time at all? If so, then you'll love "The Monster Book of Really Hard Sudoku". The puzzles in this book are not only extremely challenging, but they are extremely large, so they won't cause any eye strain while you play. Plus, this book also makes the perfect gift because it has 500 puzzles, making it the biggest large print sudoku puzzle book on the market!