They consistently ooze molten lava from their bodies, as if it were perspiration. The heat from their bodies could be sensed from 30 feet (9.1 meters).
They attacked using their claws and a breath weapon. Their breath weapon consisted of a molten blob of lava which hit a single designated target. If they were encountered in a volcanic region, they regenerated health every few seconds. The touch of a lava mephit automatically dissolved materials such as wood at a slow pace, but melted metal is a matter of seconds, such as plate mail.
They had the ability to shapechange into a pool of molten lava, and even gate in other mephits of a random type. If they came into contact with large quantities of water, they would harden and move half as fast. This had a down-side for those using this tactic: the contact of the water with the mephit would release a large amount of sulfurous steam, poisoning and nauseating the opponents.
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