The Vulshok are a culture of passionate artificers and fierce warriors that share the Oxidda Mountains with the goblins. Their look, defined in part by concept artist Matthew Wilson, includes the metallic spike-growths in place of hair (see Tears of Rage) and, of course, their spiky gauntlets (see Feedback Bolt).
In Matt Wilson's concept sketches, seen here to the right and below, the metallic gauntlets of the Vulshok start out "merely" as huge, heavy, iron, forearm- and fist-coverings. But when these mountain-dwellers enter a state of barbarian rage, the gauntlets glow with volcanic energy and they unfurl into deadly weapons.
Vulshok concept art by Matthew Wilson