System_C is a time-based drawing machine, a self-organizing software system for the creation of rule-based images. Autonomous agents move over a surface, making marks as they move. System_C draws its images slowly enough to be perceived as nearly static, yet is in reality in a process of slow development. Each image takes an hour to complete. Once an image is done, the surface is cleared, the system is set to a random initial state and the drawing process starts over.