Support materials with shader effects such as normal mapping, water, environment mapping, proxies, etc.Silly Valve! I guess I'll just have to leave it as is.
I myself think the diffrence between the difficulty levels are quite annoying. I prefer the way they did it in quake2, the harder the skill is the more enemies.Which would be a general sign that the engine can handle absolutely no A.I. at all, as well as an indication that its poorly designed. That type of difficulty standard should be relegated only to the arcade.