Fire Form. The elemental can move through a space as narrow as 1 inch wide without squeezing. A creature that touches the elemental or hits it with a melee attack while within 5 feet of it takes 5 (1d10) fire damage. In addition, the elemental can enter a hostile creature's space and stop there. The first time it enters a creature's space on a turn, that creature takes 5 (1d10) fire damage and catches fire; until someone takes an action to douse the fire, the creature takes 5 (1d10) fire damage at the start of each of its turns.

Illumination. The elemental sheds bright light in a 45-foot radius and dim light in an additional 45 feet.

Water Susceptibility. For every 5 feet the elemental moves in water, or for every gallon of water splashed on it, it takes 1 cold damage.

Death Throes: When the elemental dies, it explodes, and each creature within 30 feet of it must make a DC 17 Dexterity saving throw, taking 56 (16d6) fire damage on a failed save, or half as much damage on a successful one. The explosion ignites flammable Objects in that area that aren't being worn or carried.

Multiattack. The elemental makes two slam attacks.

Slam. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage and 9 (2d8) fire damage. If the target is a creature or a flammable object, it ignites. Until a creature takes an action to douse the fire, the target takes 5 (1d10) fire damage at the start of each of its turns.

Flame Burst (Recharge 6). The fire elemental conjures an explosion of fire in the area. the elemental chooses a point within 150 of it, which explodes into a sphere of a radius of 20 feet. Each creature in the area must make a DC 17 Dexterity saving throw, taking 56 (16d6) Fire damage on a failure, and half as much damage on a successful save.