Generic Legions is a set of free wargames rules for science fiction warfare. This versions is, as the headline suggests, for big battles.
Rules: Science Fiction
Frontline Skirmish Game For MegaBlox
“a versatile, yet simple turn-based strategy game that is fully customizable. The game is designed to make use of Mega Bloks Halo sets, but you can use any kind of equally-sized figurines including cheap army men, and is meant to be played on any kind of table or flat surface. Similar to games like WarHammer 40k or even chess, Frontline Skirmish contains very loose, simple rules and maximum customization.”
The game is on the pay-what-you-want model.
HOTT For Science Fiction
HOTT For Science Fiction is a set of troop types and amendments for use with the popular Hordes Of The Things.
Rabbidgerbal’s Super Simple 1PG Sci-fi Skermish Rules
Rabbidgerbal’s Super Simple 1PG Sci-fi Skermish Rules is a set of free wargames rules meant as a 40K replacement.
Yes, that’s really how the author spelled “Skirmish”
Space Fury Easy Starfighter Combat Rules
Space Fury are a set of quick and dirty space fighter combat rules.