If you enjoy Sudoku or play Mahjong, 108 could be your new favorite game! 108 has a special game board that evolves into a unique number puzzle during game play. The solution to the puzzle will be restricted by two groups of numbers which cannot be moved or removed from the game board once set by the players: A) Any number on a black “Shadow” square placed during game play. B) Any number on a white “Tiger” square placed during game play. To win the game, you must be the first player to fill all twenty-one squares in your row, column and block, each with the numbers 1 through 9, solving your piece of the puzzle. Like Sudoku, no number can be repeated in your row, column or block. Additionally, your numbers cannot repeat any black number in the same row or column. Designed for 4 players,yet playable with 2 or 3 as well. —description from the designer