An Artblog.

For this design we're keeping the following points in consideration

Should not have a clear 'correct' way up if it's a rolling boulder

Eyes need to be reasonable for rolling around

No visible flesh

Mouth for bite attack

Gems and metal shards like barnacles

Method to get un-stuck when rolling

So, in order to give the little guy (I may say little, but this guy is maybe 5ft tall!) a workable body shape, we're going to take some inspiration from Mexican Jumping Beans. Sure, it has earth glide to move about, but taking inspiration from the natural world is a great way to lend interest to a design. We're giving them a few flat-ish sides so that its not impeded while rolling (like bean!), but still has options to wiggle up slopes if needed (like bean!!!). I've also designed it with slight fissures to imply that the outside of the creature is made of plates- just to give it wiggle room if it needs more leverage.

Now, this guy is spending all day rolling around, but it also has an eye that it notably sees with (remember, no blindsight, only darkvision). A lidded eye wouldn't be much help while rolling, so we're forced to consider an eye that would survive the punishment of rolling around the elemental plane of earth. The only reasonable answer I can think of is a tough, crystalline eye so it can stay open while moving. As for how it sees while rolling about is anyone's guess - perhaps it stabilises in its socket? I've also opted for a triangular pupil to help confuse which way is supposed to be up on this creature, in spirit of it being a little rolly boy. The pupil is slitted due to the darkvision note. Think cat eyes.

We also have a mouth to think about. I've made this a trap-door-sort-of mouth, as a hinge risks popping open while rolling. Now, as an elemental I don't really need to think about the biology of this part too hard, but in my head (and perhaps against the spirit of being an elemental) there is a fleshy rope in the centre coming down from the eye which pops the whole thing open in order to scoop rocks into its stomach. And then maybe it rock tumbles it down into something digestible or something.

Like, why else would it have a mouth if not to eat?

Finally, we need to consider the coating on the... carapace? I guess? I've stuck on some rocks, some small gems (the same colour as the eye, just to keep the palette cohesive) and also some shellfish-looking shards of rusty metal. I thought about just adding patches of rust, but leaning into the mention of barnacles and stylising it a bit really makes the metal pop at something interesting, I think. And then I slapped on some algae-ish bits to really sell it. Don't ask me what it actually is though.