Dr Gareth Moore Mensa Killer Sudoku: More than 200 of the most difficult number puzzles* Spill Og Aktiviteter

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.