For more than a decade, a group of fans has been working on Lambda wars, a real-time strategy game set in Half life universe. Originally a Half-life 2 mod, and later a standalone beta version, the thing is already finished, or as finished as a game is these days, anyway.
Having started development in 2007, the team announced the release of v1.0 on Sunday, noting how it has “progressed from a proof of concept to an asymmetric RTS game complete with single-player, cooperative, and multiplayer game modes.”
Version v1.0 added new units, buildings, bug fixes and remodels and is available free of Lambda Wars’ Steam Page.
I remember playing this length long ago and digging, while Nathan played the game in 2014 and wrote about it on the site. Perhaps the most interesting thing about this is, as they say, its “asymmetric” nature. The (human) rebels are completely unable to compete with the overwhelming military might of Combine in a direct encounter, so the two factions play completely differently.