Ancient automated systems are traps, computer codes, old clockwork, ancient machines, or other elements put into place long ago that lay waiting to be activated. They may have been put into place by an ancient civilization. They may be triggered when a pressure plate is stepped on, when a tripwire is sprung, when a sacrifice is made, during an infrequent celestial event such as planetary alignment or full moon, or after other events. Often in narratives these systems are triggered accidently by characters exploring a strange new location. These mechanisms may seal off exits, open doors, release guards or beasts, rearrange the architectural layout of a building, start a cleaning program, or accomplish other things. They may be ancient defense systems. Ancient automated systems may be found in in ancient temples, ruins, ancient alien structures, or buildings designed by mad architects.