https://www.gamespot.com/articles/grab-this-free-strategy-game-on-humble-but-hurry/1100-6459032/

Bargain hunters who appreciate a good strategy game are in luck, because Galactic Civilizations II: Ultimate Edition is currently free on the Humble Store. You can grab your Steam code here--but do it quickly, because the game goes back to its regular price of $20 on Saturday, May 19.

Galactic Civilizations II is a PC strategy game from 2006 that's set in a future when humans have ventured out and colonized other planets. Unfortunately for us, several races of aliens had eyes on the area where we set up shop. Cue an intergalactic war of civilizations. Your job is to lead humanity on its quest to conquer the stars. To that effect, you must manage resources and deploy forces in order to defeat (or befriend) the enemies through military conquest, cultural domination, alliance, or technological supremacy.