Darwin

Darwin is an early programming game in which two or more users must try to conquer the arena (a segment of the computer's memory). The rules are governed by a program called the umpire which determines which functions can be called. Programs can probe memory locations, kill opposing programs and copy themselves to empty memory locations. The game ends after a set amount of time or when only one program (and its copies) remains alive. A limited number of memory allocations in a program can be set up as protected. When probing a protected memory allocation, the probed program would become active (until that program again hit a protected memory allocation).