M.U.L.E. was my favorite game that was ever developed for the Atari. It was on a disc, not a cartridge. It was released by Electronic Arts in 1983 when the company was new. Obviously, it looks primitive today but it was great for its time. It was later made for the Commodore 64 and other systems.
M.U.L.E. was a multiplayer game where players could develop land parcels they owned on the planet IRATA. There could be random events like fires or sunspots that could help you or hurt you. There were no weapons or people getting killed.
Review in Byte magazine