The Must Have 2017 Sudoku Puzzle Book is a collection of 200 Sudoku puzzles with VERY HARD Difficulty. This book is designed for skilled & experienced players and help keep your brain cognitively fit, flexible, and young. Sudoku puzzles add a fresh challenge to your mental workout. Although they are number puzzles, they do not require math skills. The objective of these crosswords without words is to place the numbers 1 through 9 only once in each horizontal row of squares, each vertical column of squares, and each 3x3 square box in the 9x9 grid. The puzzles have some numbers filled in, and you work out the rest. You never have to guess; all the puzzles can be solved by logic. Whether you are new to Sudoku or craving a fresh challenge, This Sudoku Book will give your brain a healthy workout. Answers for each Sudoku puzzle are included.