Even more interaction--this time used in combination with other procedures...and a lot more heavily than in the first book.

The difficulty level soars, as even more tricks get added to the mix: X-Wing; Swordfish; XY-Wing; XYZ-Wing; and the Gordonian Rectangle.

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Here it comes: a revolution in sudoku solving! This is by far the most complete guide to cracking these addictive puzzles ever produced, with tricks even the ex

The vast majority of sudoku puzzles that are labeled hard, expert, challenger, are not really all that difficult. And in a surprising number of cases, they are