White Belt Sudoku Author:Michael Rios With a separate sudoku book for every level, all puzzle lovers can play this wildly popular, incredibly addictive game that's appearing in major newspapers all over! Taking a page from karate -- another Japanese art -- each title is graded by colour: White Belt for easy, Green Belt for medium level, Brown Belt for hard, and Black Belt for th... more »e super-tough solvers. And because each book has an amazing 300 puzzles, the fun can go on for hours.« less