It depends on your environment, but basically add stereotypical things.
For examples:
Forest:
Bumpyish ground
Lots of trees
Maybe a pond or two
Snowy Forest:
Bare trees
Iced over pond
Falling snow (if a particle system is introduced)
Desert:
Cacti
Lots of sand (into the distance)
Rolling dunes
Urban:
Tall buildings with lots of windows
Unaccessable cross streets
Trashcans, signs, benches on sidewalks
Mountain:
Drop offs into a forest
Steep sides
Maybe a valley?
Etc.
Hope this helps |