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 at the top level—every one of the 320 puzzles is rated "difficult." Good luck!
Nikoli Publishing, the premier Japanese puzzle and game company, holds the trademark on Sudoku in Japan, and supplies 100 percent of the puzzles published in Japanese newspapers and magazines. Maki Kaji, the “Godfather of Sudoku,” is president of Nikoli and is credited with giving Sudoku its name.