The Times Super Fiendish Su Doku Book 6: 200 Challenging Puzzles From The Times in Bloomington, MN

These are previously unpublished quality Su Doku grids from the puzzle providers to The Times, and help to develop you to take on Extreme Su Doku. The 200 puzzles in this collection of treacherously difficult puzzles will stretch even the most advanced Su Doku enthusiast, and are guaranteed to provide hours of mind-stretching entertainment.