Mensa Killer Sudoku : More than 200 of the most difficult number puzzles by Dr.Gareth Moore

Test your powers of deduction against more than 200 devilishly difficult Killer Sudoku puzzles. The revered intelligence organisation, Mensa, have worked with Gareth Moore to put together a supreme test of logic. These brand-new puzzles will provide hours of entertainment for anyone who enjoys a difficult mental challenge.
Binding: Paperback / softback