If most Sudoku puzzles are too easy for you - Get this book of 200 Hard Puzzles for a real challenge.

• IMPROVE YOUR SKILLS You can practice solving puzzles that require: X-Wing (20), XY-Wing (70), XYZ-Wing (20), XY-Chain (70), and Coloring (20) logic techniques. A puzzle may not seem very difficult as you start it, but just wait 'til you reach the spot that requires an advanced technique


• LARGE PRINT - 2 big puzzles per page give you room for listing candidates. Even the solutions at the back are large print.


• EXTRA WIDE INNER MARGINS make it easier to fold back the book or tear out pages when you are on-the-go.


• STURDY WHITE PAPER increases visibility and holds up well when you erase.