Dwarf Fortress - Dwarf Fortress is a single-player fantasy game with two modes: fortress and adventure.
0 A.D. - 0 A. D. is a free, open-source, historical Real Time Strategy (RTS) game currently under development by Wildfire Games, a global group of volunteer game developers. Download 0 A. D.
RimWorld - RimWorld - A sci-fi colony sim driven by an intelligent AI storyteller.
Age of Empires - Age of Empires is the critically acclaimed, award winning Real Time Strategy (RTS) game with a legacy spanning over 20 years and nearly a dozen titles in the franchise.
Terraria - Dig, Fight, Build! The very world is at your fingertips as you fight for survival, fortune, and glory.
Stronghold - Stronghold Crusader is a RTS game from the series from Stronghold.