The creature design and quality of the work is AWESOME! Seriously good monster. The ONLY thing I would say, is that he doesn't look quite "rocky" enough. Although, I'm not sure if he's a monster made of rock, or just a monster who lives in the rocks. If it's the latter, then forget what I said.
Hey big guy, what you up to tonight? He's missing something though, can't quite put my hand on it, why doesn't anyone use anatomy to complete these beautiful pictures, it doesn't have to be nasty or out of control, it can be done with style, look at Michelangelo's David unless it's a girl of course, still Amazing