The puzzles, either 6 x 6 or 9 x 9, look like Killer Sudoku games but in addition to numbers, players also contend with math operators (+ - × ÷) within “fences” on the puzzle. Players arrive at the total at the top left of the fenced area by using the operator on all the numbers within the fenced area. Although the solution is a valid Sudoku solution, Kendoku numbers are allowed to be repeated within a fenced area as long as the result doesn't break the rules for a valid Sudoku.