[Guitar Woman]

As much as I don't like Half Life, I have to admit that I think Opposing Force is motherfucking fantastic. It totally makes up for the lame engine by having way less platforming and way cooler weapons/environments/enemies/characters/dialogue/everything than the original game. The fact that it was mostly developed by Gearbox rather than Valve might have had something to do with this, but that's just speculation on my part!