Killer Su Doku is based on the traditional Su Doku grid with the same rules and digits 1 to 9. Every column, every row and every 3x3 box must contain those digits 1 to 9. The main difference is that a Killer Su Doku grid contains no traditional clue numbers — only cells linked by dotted lines with a number printed in the top left-hand corner.

The joined squares must be filled with the numbers 1 to 9 that add up to the printed top left-hand figure.

Hints to solve Killer are hidden in the joined squares where only one combination of numbers is possible. In the case of two joined squares, if the printed number is 3, it should be 1 and 2 that go into the squares; if the number is 17, the combination should be 8 and 9. Likewise, in the case of three joined squares, if the printed number is 6, the only combination possible is 1, 2 and 3; if the number is 24, 7, 8 and 9. It is best to start by solving the joined squares with the lower-value printed numbers and then gradually move on to those with larger printed numbers.

EXAMPLE (Puzzle 1175 - Deadly)

SOLUTION (Puzzle 1175 - Deadly)

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