Are you ready to rise to the ultimate brain-training challenge? If so, Colormazen Very Hard Sudoku Puzzle Book will be your perfect take-anywhere companion. With 100 very hard puzzles guaranteed to sharpen your mind and keep you thoroughly entertained, this collection is a real treat for anyone who loves Sudoku. Working the puzzles in this book can provide a vigorous mental workout for virtually everyone from teenagers to senior citizens, all while fitting within the theme of Sudoku. Included in Colormazen Very Hard Sudoku Puzzle Book - Volume 7 100 Very Hard Sudoku Puzzles Printed one per page. In a large 8.5" x 11" book. -- And so much more! Activate your brain cells and grab a pencil - Colormazen Very Hard Sudoku Puzzle Book - Volume 7 is here to provide you with hours of challenging entertainment, one page at a time!