Wow, I really like Half Life, but not this much..but I thought DooM 3 was a far better game. Environmentally, HL2 played like a rail shooter in most areas. But the whole look of being set in eastern Europe somewhere really did it for me. Now, for level design, shit, DooM hands down. As far as what's been argued here, facial animations...HL2 all the way. You could really see the people were in a vast conflict worsening day by day.