Bound Inferno

superheated armor. A creature that touches the elemental or hits it with a melee attack while within 5 feet of it takes 20 (2d10) 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

Illumination. The elemental sheds bright light in a 20-foot radius and dim light in an additional 10 feet.

Water Susceptibility. For every 5 feet the elemental moves in water, or for every gallon of water splashed on it, it takes 2 cold damage.

Molten Touch. melee attack deals an additional 1d6+3 fire damage.

Multi attack: this monster is granted two attacks per turn.

Fireball. ranged weapon attack: +5 to hit, reach 25 feet., one target Hit: 36(8d6) fire damage

unarmed attack. melee weapon attack: +6 to hit, reach 5-ft., one target. Hit: 21 (3d6+5) bludgeoning damage.

Fire Whip: finesse, reach +10 to hit, reach 10-ft., one target. Hit: 3d4+6 Fire damage

Vent heat. radius effect: 30 ft. unless shielded, hit 45 (6d10+5) fire damage. usable only once per 3 rounds. recharge: roll 1d6. on a 4 or higher, Vent Heat  is useable again. on failure it recharges in 1d6 turns.

The Hands that feed. in reaction to taking damage from a melee attack, the attacker must make a DEX save (18) or be grabbed by the creature, dealing 2d6 fire damage. the attacker is now restrained. on their next turn they must succeed a DC 18 strength check to escape.