In this setting, evil monsters, usually from one or more parallel dimensions, roam free around the world. However, most people do not see these creatures for what they really are, seeing instead a vague approximation which is still plausible in that person's beliefs about reality. (See consensus reality.) For example, an ogre would appear to the average person as a very burly man. The player characters are somehow capable of seeing through this veil, and typically take on responsibility for defending humanity from the monsters. It originally appeared as a d20 mini-game in Polyhedron Magazine issue #150.