Conflagrate Scourge

Legendary Resistance (3/Day). If the creature fails a saving throw, it can choose to succeed instead.

Fire Absorbent. If the Conflagrate Scourge is hit with any attack that deals fire damage, the Conflagrate Scourge takes no damage and is instead healed for all the would be fire damage.

Heat Vision. Any creature that is attempting to hide via: ducking behind cover, invisibility, and/or digging underground can be perceived by the Conflagrate Scourge, unless specific requirements are met (Dm's choice). 

Multiattack. The Conflagrate Scourge can use its Frightful Presence. It then makes three attacks: one with its tail and two with its claws.

Bite. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 3d6 + 4 piercing damage plus 4d6 fire damage.

Claw. Melee Weapon Attack: +10 to hit, reach 15 ft., one target. Hit: 2d6 + 6 slashing damage plus 2d6 fire damage.

Tail. Melee Weapon Attack: +10 to hit, reach 15 ft., one target. Hit: 2d8 + 6 bludgeoning damage plus 2d6 fire damage.

Frightful Presence. Each creature of the Conflagrate Scourge's choice that is within 120 feet of the elemental and aware of it must succeed on a DC 19 WIS saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature’s saving throw is successful or the effect ends for it, the creature is immune to the Conflagrate Scourge's Frightful Presence for the next 36 hours.

Blazing Blast (Recharge 5–6). The Conflagrate Scourge exhales a ball of fire with a diameter of 10 ft., it will explode on contact with anything solid. A creature that is struck by the flaming ball must make a DC 19 CON saving throw, taking 22d6 fire damage on a failed save, or half as much damage on a successful one.

The Conflagrate Scourge has 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The creature regains spent legendary actions at the start of its turn.

Dry Land. The Conflagrate Scourge increases the temperature greatly, causing all creatures in a 120 ft. sphere around the Conflagrate Scourge to have disadvantage on CON checks and saving throws.

Tail Attack. The Conflagrate Scourge makes a tail attack.

Jet Fuel (Costs 2 Actions). The Conflagrate Scourge forms two wings of fire. The Conflagrate Scourge flaps its wings, each creature within 20 feet of the Conflagrate Scourge must succeed on a DC 20 DEX saving throw or take 2d6 + 8 bludgeoning damage and be knocked prone. The Conflagrate Scourge can then fly up to half its flying speed.