These are the most difficult Su Doku puzzles in The Times range. 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 usual 9x9 length but the interlocking boxes give you more clues - and more complexity.
With another 100 new Samurai puzzles to vex you for hours, lose yourself in the four levels of this book: 10 Easy 40 Mild 40 Difficult 10 Super Difficult.
Even the speediest of Su Doku solvers will be agonizing over these ultra-complex, extended brainteasers.