FreeCiv - Freeciv is an open-source, turn-based strategy game based on Civilization II.
Endless Space - Endless Space is an Amazing, Strategy, Science-fiction, Turn-based, Space, Futuristic, Exploration, Co-op, Single and Multiplayer Space Simulation created and published by Amplitude Studios.
Freeciv for Android - Port of Freeciv to Android - similar to Civilization series.
Stellaris - Stellaris is an Adventure-based, RTS (Real-time Strategy) Space, Sandbox, Sci-Fi, Single and Multiplayer video game created and published by Paradox Interactive.
Widelands - Widelands is a free, open source real-time strategy game with singleplayer campaigns and a...
FreeOrion - FreeOrion is a turn-based space empire and galactic conquest (4X) computer game being designed and...