Auntyrsurrjharontor

Legendary Resistance (4/Day). If Auntyrsurrjharontor fails a saving throw, it can choose to succeed instead.

Metallic Awakening (Recharges after a Short or Long Rest). If Auntyrsurrjharontor would be reduced to 0 hit points, its current hit point total instead resets to 450 hit points, it recharges its Breath Weapon, and it regains any expended uses of Legendary Resistance. Additionally, Auntyrsurrjharontor can now use the options in the “Mythic Actions” section for 1 hour. Award a party an additional 120,000 XP (240,000 XP total) for defeating Auntyrsurrjharontor after its Metallic Awakening activates.

Unusual Nature. Auntyrsurrjharontor doesn’t require food or drink.

Innate Spellcasting. Auntyrsurrjharontor's passive spellcasting ability is Charisma (spell save DC is 20). Auntyrsurrjharontor can innatelly cast the following spells, requiring no material components.

At will: control flames, create bonfire, fire bolt, guidance, light, thaumaturgy

5 uses p/ long rest: bless, cause fear, ceremony, command, comprehend languages, cure wounds, detect evil and good, detect magic, detect poison and disease, find familiar, guiding bolt, identify

4 uses p/ long rest: aura of life, aura of purity, aura of vitality, banishment, beacon of hope, calm emotions, conjure minor elementals, daylight, dimension door, dispel magic, divination, fireball, flock of familiars, flaming sphere, mass healing word, polymorph, remove curse, revivify, wall of fire

3 uses p/ long rest: commune, contact other plane, dawn, flame strike, forbiddance, hallow, heal, legend lore, mass cure wounds, planar ally, reincarnate, sunbeam, wall of light, raise dead

2 uses p/ long rest: conjure celestial, control weather, crown of stars, delayed blast fireball, demiplane, divine word, holy aura, plane shift, regenerate, resurrection, sunburst, teleport

1 use p/ long rest: gate, mass heal, true resurrection 

Multiattack. Auntyrsurrjharontor makes one Bite attack and two Claw attacks.

Bite. Melee Weapon Attack: +18 to hit, reach 15 ft., one target. Hit: 21 (2d10 + 10) piercing damage plus 13 (2d12) force damage.

Claw. Melee Weapon Attack: +18 to hit, reach 10 ft., one target. Hit: 19 (2d8 + 10) slashing damage. If the target is a Huge or smaller creature, it is grappled (escape DC 20) and is restrained until this grapple ends. Auntyrsurrjharontor can have only one creature grappled in this way at a time.

Tail. Melee Weapon Attack: +18 to hit, reach 20 ft., one target. Hit: 21 (2d10 + 10) bludgeoning damage. If the target is a creature, it must succeed on a DC 26 Strength saving throw or be knocked prone.

Breath Weapon (Recharge 5–6). Auntyrsurrjharontor uses one of the following breath weapons:

Elemental Breath. Auntyrsurrjharontor exhales elemental energy in a 300-foot cone. Each creature in that area must make a DC 25 Dexterity saving throw, taking 84 (13d12) fire damage on a failed save, or half as much damage on a successful one.

Sapping Breath. Auntyrsurrjharontor exhales gas in a 300-foot cone. Each creature in that area must make a DC 25 Constitution saving throw. On a failed save, the creature falls unconscious for 1 minute. On a successful save, the creature has disadvantage on attack rolls and saving throws until the end of the greatwyrm’s next turn. An unconscious creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Change Shape. Auntyrsurrjharontor magically transforms into any creature that is Medium or Small, while retaining its game statistics (other than its size). This transformation ends if the dragon is reduced to 0 hit points or uses its action to end it.

Auntyrsurrjharontor can take 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. Auntyrsurrjharontor regains spent legendary actions at the start of its turn.

Attack. Auntyrsurrjharontor makes one Claw or Tail attack.

Wing Attack (Costs 2 Actions). Auntyrsurrjharontor beats its wings. Each creature within 30 feet of it must succeed on a DC 26 Dexterity saving throw or take 17 (2d6 + 10) bludgeoning damage and be knocked prone. Auntyrsurrjharontor can then fly up to half its flying speed.

If Auntyrsurrjharontor’s Metallic Awakening trait has activated in the last hour, it can use the options below as legendary actions.

Bite. Auntyrsurrjharontor makes one Bite attack.

Shattering Roar (Costs 2 Actions). Auntyrsurrjharontor unleashes a magical roar. Each creature in a 120-foot-radius sphere centered on Auntyrsurrjharontor must succeed on a DC 26 Constitution saving throw or take 19 (3d12) thunder damage and be incapacitated until the end of its next turn.