Xenocide: Firefight is an update of the older Xenocide rules. It is a game of sci-fi miniature combat, based on squads of individuals. It will be best played with 15mm or 28mm figures. At those two scales, I would keep all movement and firing ranges the same. If you wanted to have a larger game area, you could halve all of the ranges, but it will make for a longer game (not necessarily a bad thing).
Designer: Thane Morgan
Link to Rules[]
http://web.archive.org/web/20070815155806/http://www.thanesgames.com/firefight/xffmain.htm