Savage Sudoku: 140 Puzzles to Test Your Skills (Dover Brain Games: Math Puzzles)

Sudoku enthusiasts, rejoice! Here's a collection that features scores of engrossing puzzles that promise to truly test your skills. Created by Terry Stickels, a nationally syndicated puzzle-maker, the challenges range in difficulty from medium and hard to very hard and extremely difficult. Don't worry if you're truly stumped ― complete solutions appear at the end of the book.