The fourth instalment in the fiercely popular, bestselling Fiendish Su Doku series. A new collection of previously unpublished Fiendish Su Doku puzzles with the added bonus of 25 Super Fiendish puzzles. Perfect for the advanced solver in need of a constant supply of ultra-difficult puzzles, and guaranteed to provide hours of absorbing, brain-stretching entertainment. The puzzles in this collection are of the highest quality and supplied by Puzzler Media, the Su Doku suppliers to The Times newspaper. Since the first Su Doku puzzle appeared in The Times in November 2004, they have become a phenomenon, with over 5 million copies of The Times Su Doku books sold worldwide. You don't need to be a mathematical genius to solve these puzzles; it is simply a question of logic. Each puzzle has a unique solution - and there's no guesswork required. The Times Su Doku remains the original, the best and the market leader.