A new mass market edition of the USA Today bestselling series.USA Today and Los Angeles Times bestsellers and featured in Entertainment Weekly"s "Must List," The Big Book of Su Doku series includes original puzzles from easy to extreme, for users and addicts of all ages. The Big Book of Su Doku #3: Extreme is not for the faint of heart, with 200 puzzles that take Su Doku to a new level with classic 9 x 9 grids ranging in difficulty from "tricky" to "diabolical," and new Maxi, Jigsaw, Super, Duplex, and Super Triplex puzzles.