Looking for a new challenge now that you've mastered sudoku? Kakuro might be just what you need, and Kakuro For Dummies is a great place to start A kakuro puzzle is a grid consisting of interlocking horizontal rows and vertical columns of squares, called blocks. You fill in the empty squares with numbers that match the clues and work both horizontally and vertically. Sound simple? Guess again Kakuro uses the logic of sudoku plus some basic...