2,002 Really Hard Sudoku Puzzles

Sudoku puzzles are a tantalizing challenge - and an excellent way to develop and utilize your logical thinking skills. This publication is not for beginners - or those who are faint of heart. It presents 2,002 really hard 9 x 9 Sudoku puzzles that will truly challenge you. The first 1400 are traditional puzzles that contain the numbers 1 through 9. The final 602 puzzles contain letters and symbols, which will test your ability to use your Sudoku wisdom with non-traditional characters. If you consider yourself a true Sudoku master, this book will give you countless hours of invigorating - and challenging - fun.