This book contains 100 SUDOKU puzzles of varying difficulty, meant to take you to a journey of discovery and eventually mastery of this century's most addictive game. There are plenty of puzzles for you to enjoy: There are 100 Hard puzzles, if you want a real challenge. Whatever you´re looking for, there´s something for you in this Sudoku Book. Good luck and play! Keep your brain fit, young, and flexible!