Death Blast. When the fire bat dies, it explodes in a burst of lava. Each creature within 5 feet of it must make a DC 16 Dexterity saving throw, taking 17 (5d6) fire damage on a failed save, or half as much damage on a successful one.

False Appearance. While the fire bat remains motionless, it is indistinguishable from an ordinary mound of magma.

Innate Spellcasting.(3/Day). The mephit can innately cast heat metal (spell save DC 15), requiring no material components. Its innate spellcasting ability is Charisma.

Claws. Melee Weapon Attack: +7 to hit, reach 5 ft., one creature. Hit: 10 (2d6 + 4) slashing damage plus 3 (1d6) fire damage.

Fire Breath (Recharge 6). The fire bat exhales a 30-foot cone of fire. Each creature in that area must make a DC 16 Dexterity saving throw, taking 17 (5d6) fire damage on a failed save, or half as much damage on a successful one.