Alien Swarm long way down effect?

Heya guys does anyone know how to make the effect like when you’re on aplatform and you can see a long way down?

It fades to red and there’s smoke and stuff…

Also do you know some good lighting settings?

env_fog_controller Probably

[editline]11:20PM[/editline]

“smoke and stuff” is probably props and particle systems

It’s env_fog_controller. Check out the Landing Zone vmf for how they did the rest of it.