Half Life set a benchmark for single player that even modern games can't touch *coughUnreal2cough*. Sure, it's dated now, but most people who had the pleasure of playing when it was brand new, know how kick ass it was. Look how old it is, and it still sells thank to CS and other mods.
I will say that the multiplayer sucked bad IMO, but I was busy with Q1/Q2 anyway.
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He cut the possum's face off then cut around the eye socket. In the center of the belt buckle, where the possum's eye would be, he has placed a small piece of wood from his old '52 Ford's home made railroad tie bumper. Damn, he misses that truck.