Su Doku Silver is the second title in a new series of books from the Su Doku master, Wayne Gould. Continue the race to master Su Doku at every level with this Mild collection of puzzles, guaranteed to entertain and challenge you at a relaxed pace. The original creator of The Times puzzles, Wayne Gould is the leading authority on Su Doku and is the man responsible for transforming this Japanese number puzzle into a worldwide phenomenon. Gould's success resulted in him being listed as one of Time magazine's most influential people in 2005. Containing 150 previously unpublished puzzles, Su Doku Silver follows on from Su Doku Bronze and is the second of four collections designed to exercise the brain and test your logic.