PopsiGames
Warzone 2100 is a real-time tactics and strategy game. You build a base, research technologies and design your own units by combining chassis, weapons and propulsion, then lead them in battle across a ruined world.
It has a full campaign, skirmish games against the computer and online multiplayer. The research tree is large, so the way you play can change a lot from one match to another. Many community maps and balance mods exist.
The game was released commercially in 1999 and later released by its developers as open source under the GPL, and it is still maintained by volunteers. There are no ads and no purchases.
