Recently I've bought some rolling pins and some clay as I want to start doing some scenery for the game (I have yet the big rocks and now I want more!)
So over a DM base I've extended a layer of clay, passed a rolling pin with a cracked earth pattern and oven it to harden the clay. I've glued some little rocks and a plastic skull.
For painting I have used the airbrush. Black primer all over the base and some red, orange and yellow on the fissures. Finally a glossy varnish only on the fissures.