Killer Sudoku Daily Competition. Advance puzzles are now available Anyone can get into the Top Sudoku Expert list - this is now the sum of all your correct. Welcome to Killer Sudoku - a logic puzzle with very simple rules and challenging solutions. All Puzzles A cage clue tells you the sum of the digits in that cage. Killer Sudoku (also called Sum Sudoku) are a kind of hybrid puzzle that combine the best features of Sudoku and Kakuro (cross-sum) puzzles. Like a regular.