To feed the nation's addiction further, here is the sixth installment of The Times Su Doku puzzles. Now with even more puzzles for the hardened Su Doku addict, The Times Su Doku Book 6 contains 150 puzzles, ranging from mercifully Mild to the uber challenging Super fiendish.

• 40 Mild puzzles
• 50 Difficult puzzles
• 50 Fiendish puzzles
• 10 Super fiendish puzzles

With brand new puzzle suppliers, market-leader The Times offers a whole new collection of numerical conundrums for your brain to wrangle with.