Just out of interest, when was SS2 out compared to HL?
I think that HL came out before SS2.
I remember that, at the time, the closest rival to HL was the original Unreal, which took a very different path.
Yes, Half Life was ahead of its time. It seems much less revolutionary now, in no small part due to the fact that developers have taken a lot of its features and re-done them in a variety of games. I will say one thing though: Xen sucked donkey balls and was a mistake of epic proportions

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M on and off, and the graphics arnt that bad iv seen worse in newer games.