So, came up with this idea when trying to evict a gopher from under my front step. He was not taking the hint when I kept filling in his hole so I used some fill a gap foam to fill in his burrow. Ha, it worked. Then I noticed some of the foam the rolled out/over some of the edges rounded/evened out smoothly. I took a shot and just sprayed a small amount out and let it fill out. I spray painted the results with Krylon rock texture paint. Thinking about trying this with some chicken wire and making a cave/mine something.
Now when I look at this custom, I keep thinking of the Batman episode when the villains are talking about how they "almost got him." Killer Croc's story was he threw a rock, "It was a big rock."