From compo website; "The player's task in games of this genre - to deal with the advancing enemies before they cross the map by building towers that attack them when they are near . Opponents and towers usually differ in characteristics and price . When the enemies are defeated , the player earns money or points, which are used to buy or upgrade towers. Selection of the towers and their location - an integral strategy game. Usually creepy-crawlies run through the maze similarity that enables the player to the strategic placement of towers."