Board is just plywood (a poor choice in retrospect, as the warping is a real nuisance) and some model railway static grass mats glued over the top. A cheap and easy solution to get me up and running. I want to try my hand at making a fully modular setup this year so am treating this as a learning experience
I also bought some pre-made terrain from Gale Force 9. It is quite drab, and the skulls are very poor
So I have gone over them, replacing the skulls and throwing on some extra stuff