Killer Sudoku, also known as Sum Sudoku, blends Sudoku with Kakuro. Like usual Sudoku, each row, column, and 3x3 box must have the numbers 1 to 9 once. The unique part is the shaded areas with a clue number in the corner; the numbers inside these areas must add up to that clue.
How To Play
The aim is to complete every empty square in each row, column, and 3x3 box with numbers 1 to 9, making sure each number appears just once. Adding a twist, there are 'cages' with a distinct background color and a number in the upper left. Each number in these cages must be unique, and their sum must match the clue given in the cage's top-left corner. Each Sudoku puzzle has one correct solution.
