Gut Check Solo 15mm Science Fiction Rules v1.7

Gut Check is a set of free wargames rules for 15mm science fiction battles. What makes it unique, I think, is that it’s designed from the start for solo play. The author lists its features:

Designed from the ground up for solo play
Fast playing and zero bookkeeping
Uses normal 6 sided dice (Usually rolled no more than 2 at a time)
Uses activation rolls modified by battlefield conditions for turn sequence
Seamless Over watch and suppression effects built into system
Use any miniatures
Played on a Hex grid for convenience, but could be played with little fuss on a standard table

Foundry Street Violence Rules

Some years ago, Wargames Foundry published a set of rules to go with their Street Violence figures. They’re missing — as far as I can tell — from the Foundry site, but you still can get them as a free download at The Warstore.

Legends of Dying Mars John Carter Skirmish Rules Set

Legends of Dying Mars is a set of free skirmish rules for playing games set in the classic Edgar Rice Burroughs John Carter of Mars Barsoom setting.

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The AD Wars Science Fiction Rules

The AD Wars is a set of free wargames rules that are adaptation of Warhammer Ancient Battles for science fiction games. It’s interesting. You will need a copy of Warhammer Ancients to play, though. But there are a lot of copies of that out there.

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FUBAR One Page Modern / Science Fiction Rules

Fubar is a good looking one page set of modern and science fiction rules.