Killer Sudoku Puzzles to Drive You Mad!

If you like Sudoku but are ready for a new challenge, look no further- Killer Sudoku is what you want! Killer Sudoku offers a twist on normal Sudoku. You still write numbers 1-9 in different boxes, but this time you use simple math to figure out where to write each number. Also, the regions are usually a random arrangement of squares, not always 3x3! Inside you'll find 104 Killer Sudoku puzzles in four different levels of increasing difficulty. Good luck! Killer Sudoku is also calld Sumdoku, Addoku, and Samunamupure.