Times Samurai Su Doku 12: 100 extreme puzzles for the fearless Su Doku warrior

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 Do...