Clockwork Elephant would be cool...
Of course, we already have Iron Dragon...
Another possibility for Nature could be (I think I mentioned it before in some other thread) just an intelligent Elephant with some weak magic for self-buffs. Think The Mountain That Walk...
A development of earlier thought of Aezeal: if we want to make an "anti-SC" it can have a good number of low-damage attacks. Variants:
Poltergeist: Astral or maybe Death, Ethereal creature, description states that it attacks by throwing various objects telekinetically. May get Sticks & Stones as a missile attack, but main would be "Thrown Objects" attack with high multiplier and low damage. Only miscellanrous slots, obviously. May be stealthy, though it's not necessary.
Chain Elemental (or somethin suitably impressive-sounding, there was some DD monster of such general nature and I believe that there was some movie where it appears 1st): Earth(?). Looks like humanoid figure totally wrapped in chains. Controls those chains, making them flail around striking his opponents. Obviously quite good protection. Possibly entangle defense (or secondary effect of attack?)