New York Post Pure Evil Su Doku: 150 Fiendish Puzzles
The official utterly addictive number-placing puzzle
Look out: these Fiendishly tough puzzles are pure evil. Don't say we didn't warn you. More than just hours of entertainment, Su Doku engages your mind, improves your concentration, and helps you stay mentally fit. If you can make it through these 150 brand-new puzzles, you'll be an indisputable Su Doku master.