Mini Volcano

This is scenery, not a hazard. It sits in the corner of a room puffing away and throws off a small amount of light. The part worth knowing is that the animation answers to wiring, so you can run it off a switch or a timer and have it start and stop on cue, which most decorative furniture cannot do at all.

You will end up with spares without trying. It comes out of the crates you fish from lava, so anyone farming those for ore and gear collects a pile of volcanoes on the side.