Just when you thought it was safe to pick up a pencil Killer Su Doku is based on the original Su Doku grid, with the same rules and numbers—1 to 9—but with

This is Su Doku multiplied: every column, row and 3x3 box must contain the digits 1 to 9. Where the puzzles overlap, the rows and columns do not go beyond their

Killer Su Doku poses an even greater challenge than the Fiendish Su Doku puzzles.Here are 100 previously unpublished puzzles for hard-core Su Doku addicts.

Push your nerve and logic to the absolute limit with this third collection of The Times Killer Su Doku.