This was done for the rift colossus contest. It is following the planar theme death. took me 5-10 hours, generously guessing. done in photoshop. Im very happy with this one. hope you all like it. Any construvtive criticism is welcome.
Nice idea I think to improve upon this I'd change the whole composition to show the scale of the creature, perhaps some worms eye view from the little guys level, with the monster towering above. The other thing that holds this back a little is the lighting, it's not really consistent across the whole scene, and could be used to add more drama (I take it the light is coming in from the holes in the ceiling, this could make for interesting patches of light and dark shadow). Also as I mentioned in another crit, the rocks don't look like rock, those real world studies might be very useful for you