Overall, this has potential. Too limiting in the pose though. Nice horn idea. Of course as a flight of fantasy it works, but if you through bio-mechanics into the mix you have issues.
The legs and tail make for awkward balance and those are going to have to be some impressive wrists to fly. Especially when he raises his arms and hits his own horns. If he just runs along the ground shaking those wings like a big scary flags, then it’s probably not bad, but I don’t thing the little feet will do it.
You need more detail work, close up it loses what you tried to achieve. Try inflate and other brushes with your masks so everything doesn’t look like it’s stuck on.
Like I said, if you’re going for total fantasy, it may work, but most of the good fantasy stuff takes into account some rules and then stretches them a little in all directions.
However this does have some serious potential. 