I like everything apart from the Dragon itself tbh. It just doesn't blend well with the rest of the design - whether its the lack of depth and/or detail - it just doesn't feel a part of the overall design. You've added light and shadows to practically everything besides the dragon itself, or atleast not enough for it make the dragon to stand out. It's also kind of hard to tell what angle point I am meant to be looking at this design from. For instance, if I am looking down (which can be interpreted from the size of the trees) then i shouldn't actually be able to sell the entirety of the mountain range/dragon. If i was to look at this straight on, then the trees would be larger (unless you wanted them to be small bushes or something).
The grass and trees are exceptional though :P
that's just my two-cents though