To get fog:

1. Select any brush that is not an entity but part of the worldspawn.

2. Type in key "farplane" and value "#". # can be any number you want, 1000 or 2000, etc.
	This will be the distance you can see in units before the level stops drawing geometry.

3. With the brush selected and the 2d view active (not the entity properties window), press 'k'
	to bring up the color selector. Choose a color for your fog, then click on the OK button.
	
4. You will see a "_color" key added to the worldspawn in the entity properties window. Rename the
	"_color" portion to "farplane_color".
	
5. Add a key of "farplane_fog" and a value of "1". This will make fog appear in your level.
	
6. Compile and light your map.

-Reid "BrushBaron" Kimball
brushbaron@rbkdesign.com