<p>The official utterly addictive number-placing puzzle</p><p>Give your brain a workout with these all newDifficult-level puzzles. Their addictive power willnot only entertain--Su Doku puzzles engageyour mind, improve your concentration, and helpyou stay mentally fit. There's no excuse for slowthinking and flabby wits when you can trainyour brain!</p><p>Beware of pale imitations. These are the original andofficial Su Doku puzzles by Wayne Gould--<em>New York Post</em>'sSu Doku puzzle master and one of <em>Time</em> magazine'sMost Influential People.</p>