Expert Sudoku is an all-new collection of handcrafted puzzles for the expert puzzle-solver. This is the book that challenges skilled solvers and Sudoku-lovers a

Extra tricky. Extra tough. It's the sudoku collection that's not for the faint of heart. If you're craving the challenge, sharpen your pencil and pit your wits

From Nikoli, the Japanese puzzle company that created the sudoku craze, comesa title that starts at hard and goes to a level of difficulty not seen in anyprevio

“The Best Puzzles Are Made by Happy Employees.” So Ad Age describes the credo of Nikoli, the Japanese puzzle company that invented the Sudoku craze and supp

Welcome to the 9 Circles of Sudoku Hell! From Merciless to Maddening to Murderous, this is a book to challenge even the most seasoned Sudokuist. By the end of t