Book excerpt: What kakuro fan could resist this huge collection? Featuring 940 grids in varying levels of difficulty, it has more than enough to satisfy even the most avid enthusiast. Half sudoku, half crossword, language-free kakuro is set to become the next worldwide puzzle phenomenon. The basics are simple: just fill in the empty squares using numbers from 1 to 9 so that the sum of each horizontal set of squares equals the clue on its left, and the sum of each vertical set of squares equals the clue on the top. No number can appear more than once in any sum. An introduction explains all the rules, gives good solving tips, and takes beginners through a sample puzzle.