Squares of Doom: Subtraction
Solve each of the 10 levels by filling in the gray squares to make the difference of the black squares, both rows and columns. Careful though: boxes can have a pair that must contain the same number. Give the game your best shot!
How to play
Gray - Open, Black - Total. Hover over a box. Type a number. Box A = Box A, Box B = Box B, and so on... Highest possible number is the current level. Have fun!