A single player campaign. You must fight your way to the surface of Black Mesa...
This is the HLRL version of the strogg guards found in the half-life addons category and it includes original quake 2 sounds and replaces the - ngrunt - zgrunt - massn - hgrunt to stroggs and also includes quake 2 the reckoning stroggs so here you go and enjoy :D
Fun!
Wait, there's Strogg in Residual Life?
OOTOH!
Probably not. Id say its a replacement but I'm completely uncertain.