Stones is a game developed by Michael C. Miller and released in 1991 as part of Microsoft's Windows Entertainment Pack. The object is to place 90 tiles, or "stones", on a board. A tile can only be placed if it shares two of three attributes - background color, character color, or character shape - with every adjacent tile. Wild tiles may be placed anywhere regardless of attributes. The game is won when all tiles are placed or when there are no valid spaces to place the next tile.