US Patent 7458580 Lottery game card having a Sudoku game

A lottery game card including a plurality of squares distributed in a matrix format, and a plurality of game indicia initially covered by a removable material. Each squares of the matrix are populated with a game symbol and some of the squares of the matrix are covered by the removable material, forming a Sudoku puzzle. A player may play the Sudoku puzzle using the matrix. The player may remove the removable material from the game indicia and covered squares. If the squares identified by the game indicia form a predefined pattern, a prize is awarded to the player.