From Wikipedia
Air Warrior was a multiplayer on-line air-combat simulator launched by Kesmai in 1988. It was hosted on GEnie and used that service as a server for client software running on a variety of personal computers available in that era. It underwent continual improvement through its decade-long lifetime with Kesmai, appearing on new platforms and host services.
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Air Warrior was played over modems and hosted on the GEnie online service provider. Players could choose one of a number of World War II aircraft to fly, along with ground vehicles, and play in a multiplayer "arena" with hundreds of other players. The game focused mostly on dogfighting, with a secondary strategic role of capturing forward airbases near the center of the map. Several updated versions were released, and additional service providers were added over time.