Armor Bound Fire Elemental

Fire Aura. At the end of each of the elemental’s turns, each creature in a 5-foot Emanation originating from the elemental takes 2 (1d4) Fire damage. Creatures and flammable objects in the Emanation start burning.

Fire Form (Ashen Form must be active). The elemental can move through a space as narrow as 1 inch without expending extra movement to do so, and it can enter a 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 30- foot radius and Dim Light for an additional 30 feet.

Water Susceptibility. The elemental takes 3 (1d6) Cold damage for every 5 feet the elemental moves in water or for every gallon of water splashed on it.

Molten Endurance. When they drop to 0 HP, they release a burst of superheated energy, dealing  (3d10) Fire damage. fire damage to all creatures within 15 ft. (DEX save DC 15 for half). They then reform after 1 minute with 1 HP if at least one ember remains intact.

Emotionally Reactive. Rage or grief can amplify their aura uncontrollably. 

Bound Flame (Unique Trait). Their soul is sealed inside an arcane metal shell. They cannot remove it fully without their essence destabilizing.

Multiattack. The elemental makes two Blazing Grasp attacks.

Blazing Grasp. Melee Attack Roll: +7, reach 5 ft. Hit: (1d10+4) Fire damage and (1d8) Bludgeoning damage. If the target is a creature or a flammable object, it starts burning for (1d6) Fire damage at the start of its next turn (CON Save DC 14 to extinguish).

Ashen Form (Transformation, 1/day). Their armor partially melts away, revealing their true fire elemental form. Duration: 3 rounds. Gains flight (hover 30 ft.), immunity to nonmagical weapons, and Burning Touch (auto 2d8 fire damage to any melee attacker). After ending, they become weakened, losing 10 HP and having -2 STR for 1 hour.

Soulflare Burst (Action, 3/day). They release a wave of explosive fire from their chest vents. 20-ft radius centered on them. Each creature must make a DEX save (DC 15). On a failure take (4d10) fire damage and you are knocked prone. On a success you take half damage, and are not knocked prone. Leaves a glowing scorch field that lasts 1 minute and emits dim red light.

Infernal Surge (Bonus Action, Recharge 5–6). They channel their core flame to superheat their armor and increase power. Gain +2 AC and +10 movement for 2 rounds. All melee attacks deal an extra (1d8) fire damage during that time. Elemental takes 5 fire damage each round while active (cannot be resisted).