Canyon

The foreground part is nicely done, the mountains in the background look flat and 3D. The horses are copied and look exactly the same. I would have helped to hide this fact by position them differently. As Rashad pointed out, this is not usual behaviour of horses to run to death. There is nothing that indicates why the horses should panic. The composition is good and the camera angle very fitting. Try to tweak the materials that come out of the library. All this talk is meant to help you improve, not to belittle you work.

The scenario is very well composed. There are a couple of considerations. The materisl on the distant mountains seems somehow odd, as if one mountain is mapped vertically and the other is mapped horizontally. The foreground terrain is great and I like the dead tree. The horses seem to be running in full gallop toward certain death. I think that in this case the horses should not be running toward the water below them.