Conquest is a real-time, multi-player space warfare game that was originally written in RATFOR for the VAX/VMS platform by Jef Poskanzer and Craig Leres in 1982. It was the early predecessor to Netrek.
The Romulan defense robot going to defend its home.
If you attack a team planet (Federation, Klingon, Romulan or Orion) in the home system (the triad of planets around the home suns - Sol, Kejela, Sirius or Betelgeuse) that have team armies and there is no player active (its possible to leave ships in the game, but inactive) for that team a robot will be spawned.
Meet them:
M-5 (Federation) - from the TOS episode "Ultimate Computer" - and the genesis of the robot defender idea.
Guardian (Klingon)
Colossus (Romulan)
HAL-9000 (Orion) - from 2001 a Space Odyssey.
For noobs these bots can be a real hassle. Still, they are only bots, and one bot buster strategy away from being photon torpedo bait.