Sudoku16 is complex variant of sudoku game destined for real puzzle lovers. It's also known as Suduko, Sudoko, Su do ku, Sodoku, Suduku. In it you must to compare numbers on game board to make them according the rules. Which are very elementary. Each row, column and subgrid inibox (4x4) comprises the numbers 1 through 16 or letters A through P or anything else. From kids to old can like it for a pass-time.