first of all, that's a very cool concept piece! I love the mask and head especially
it's not translating well to pixels though. I imagine that some of that has to do with the creature itself rather than your pixeling skills, which seem pretty good.
Without looking at the reference piece I had no idea what was going on besides the chest and arms. The mask looked like a white beard that got flipped up into it's face, and I had no idea what was
going on with the legs. The shading on the lower arms doesn't seem to match what the arm shape should be.
EDIT: you may want to modify your webserver settings if you don't want folks poking around the rest of your files
which I did
I think one of the other poses you did might translate better to a standalone pixel piece