For anyone who loves the challenge of Su Doku but manages to solve them
within minutes, you can now enjoy the extended mental workout and
ultimate endurance test of a five grid interlinked system. 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. These
are the most difficult Su Doku puzzles in The Times range.