Cave Thing is painted with a diver’s mask at the edges, hinting at Subnautica’s first person nature. On right right, a small vehicle of some kind if shining lights on to the evidently bemused creature. Small vehicles will be pilotable (or this one an un-manned drone, supporting the swimming player?), deploying from ‘mothership’ style larger vessels (See Exterior Sketch for more about this!).

Most importantly, this little encounter is taking place in a cave. Steve has been working hard on procedural terrain generation techniques that result in cave formations. Caves are also likely to be a regular feature of artist-created pre-fabricated areas, some of which might feature a create like the Cave Thing…
Mr. Crabs!
Nicely done concept art as always. (^_^)