I make a quick edit, as you can see in my edit, i removed the banding that i saw, but kept the lighting the same. With that i simply changed the light source, to seem more behind and to the right.
-Which makes it looks like a two dimensional cardboard.
lots of banding on the alien. and despite such a dramatic light source, the only shading on him is a white highlight coming from a different direction?
Funny creature)