The guys shadow just looks like a single colored block. Try to add some shading to it and continue the patern of the ground underneath it jsut darker. But ya like LP said, move the moon and possibly move it a bit lower too, to cast longer shadows which I feel would fit the piece better. Ther background kinda needs work too. The mountains seem to pop up and disapear quikly, maybe make it build up to them. Also the [bleep]e thing in the background is just wierd and I don't think it fits.