Fans of math puzzle games will enjoy Kakuro, a challenging Flash game that's a combination of Sudoku and crosswords. The objective of the game is to provide a group of numbers from 1-9 that add up to the target sums on the blue squares. Similar to Sudoku, each number can only be used once for a target sum. If a target sum appears in the upper right hand corner of the blue square, this means that the numbers you use will go to the right of it (Across). If a target sum appears in the lower left hand corner, this means that the numbers you use will go below it (Down).

The challenges lie in determining the right combinations and orders of numbers to get that sum. For example, if an Across target sum is 7 and there are two spaces next to it, you can use 1+6, 2+5, or 3+4. However, you can also use 6+1, 5+2, and 4+3. And just like a crossword puzzle, the numbers you use for the Across target sum has to coincide with the Down target sum. There is only one solution per board.

Kakuro offers three difficulty levels: Easy, Medium, and Hard, with randomized boards for each level. There's also a Practice level available. The board itself is very user-friendly. Clicking on the target sums brings up a list of the possible number combinations. The numbers are color-coded; green means you have the correct sum while red means you have the wrong sum. A yellow number indicates that the sum is wrong in one direction. You can type in the numbers directly or select a number from the drop-down keypad. If you're not sure of a certain number, you can mark it and return to it later. If you put the wrong number, you can always delete it or hit the Undo icon. And if you really screw up, you can clear the board and start over.

Article Author: Toni Schwartz

Toni is an Assistant Gaming Editor at Blogcritics Magazine. She's proud to be a gamer chick and a movie buff!

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