An umber hulk is a powerfully built creature that looks something like a cross between a great ape and a beetle. The low, rounded head is dominated by a massive pair of mandibles and rows of triangular teeth. It has two big compound eyes like a beetle's, with two smaller eyes like an ape's in between. Armor plates cover virtually all of its chitinous body, whose scattered feelers resemble sparse hair.
These massive creatures dwell deep beneath the earth, ripping through rock like it were light underbrush. They rampage continuously, leaving destruction in their wake. They are roughly 8ft tall and 5ft across, weighing in at nearly 800 lbs. Besides delivering blows powerful enough to crush almost any enemy, their mandibles are also strong enough to bite through most armor or exoskeletons with ease.