After a dark brown latex house paint base coat (Behr "Swiss Brown"), each piece gets a stipple and dry brush of Craftsmart "Orange Spice". This rusty reddish brown color is intended to show only as subtle hints in crevasses, and isn't done very heavily.
|Brown base, rusty red and finished piece|
Next, each piece gets a healthy sponge coat of Folk Art "Camel", my go-to light tan color for terrain. A little dry brushing gets to the spots the sponge can't easily reach. I don't want an overwhelming amount of the dark brown base showing through.
|Base coated, rusty red and "camel" sponge|
Finally, a lighter sponge coat of a very light creamy tan (Folk Art's "Taffy") is used to highlight the edges and brighten the flat surfaces. The pieces looked a little dingy before this step but popped nicely after.
|"Camel" sponge (left) without final highlight (at right)|
The final project, shown below, consists of a large two-piece hill which can be used together or separate, a bunch of larger pieces, and a good assortment of smaller pieces in both 2" foam and 3/4" foam. The 2" pieces (which are most of them) give good height and mass, and the smaller pieces allow for climbing access for figures, or just smaller scatter.
|Final pieces with "Taffy" light highlight|
This project filled a very large plastic storage box. I'm not sure how often I will have a use for them, but the materials were cheap and the whole project only took a few hours scattered over the course of a week or so. Very easy, and now I have options other than gray rock...