GORF is an acronym for "Galactic Orbiting Robot Force".
Was the first arcade game to include multiple mini-games.
The game machine actually used a speech-synthesis chip, as opposed to playing digitized samples of synthesized speech, which require more memory.
Destroying the Gorfian Flag Ship at the end of a mission series moves the player up in rank. The player starts as a Space Cadet and can be promoted to Space Captain, Colonel, General, Warrior, and Avenger. Each promotion also results in an increase of difficulty of the subsequent mission set.
Level Three of this game is called "Galaxians" and is a version of that game, but with only 24 foes instead of the original 48.