Imperial Starfire is an expansion for Starfire (3rd Edition) (1992 Edition). It included campaign rules for Starfire (3rd Edition), such as universe generation, alien races, research, economics, communications, intelligence operations, supply, etc.
The Starfire series is a series of games that simulate combat in space at sublight speed. Galactic travel is accomplished through "Warp Points" which connect star systems in a random manner. Ships are made up of various combat and non-combat systems each represented by a letter (or combination of letters). A "word" makes up a ship. Movement is on an "endless" hex map, and occurs in 6 impulses. As damage is done between ships, letters are crossed off from left to right within the "word" until the ship is destroyed.