A new title in the Fiendish Su Doku series, concentrating entirely on the more difficult Super Fiendish puzzles. These are previously unpublished quality Su Doku grids from the puzzle providers to The Times, and help to develop you to take on Extreme Su Doku.

A new title in the Fiendish Su Doku series, concentrating entirely on the more difficult Super Fiendish puzzles. These are previously unpublished quality Su Doku grids from the puzzle providers to The Times, and help to develop you to take on Extreme Su Doku.