Armor Class 20 (natural armor)
Hit Points 222 (12d20 + 96)
Speed 40 ft., fly 80 ft., climb 40 ft., burrow 40 ft.
Saving Throws DEX +7, CON +14, WIS +9, CHA +11
Skills Perception +15, Stealth +13, Survival +9
Damage Resistances cold, radiant
Senses blindsight 60 ft., darkvision 120 ft., passive Perception 25
Languages Common, Draconic, telepathy 120 ft.
Challenge 19
Legendary Resistance (3/Day). If the dragon fails a saving throw, it can choose to succeed instead.
Multiattack. The dragon makes one Bite attack and two Claw attacks.
Bite. Melee Weapon Attack: +13 to hit, reach 15 ft., one target. Hit: 18 (2d10 + 7) piercing damage plus 9 (2d8) radiant damage.
Claw. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 14 (2d6 + 7) slashing damage.
Scintillating Breath (Recharge 5–6). The dragon exhales a burst of brilliant radiance in a 90-foot cone. Each creature in that area must make a DC 22 Constitution saving throw, taking 49 (11d8) radiant damage on a failed save, or half as much damage on a successful one. The dragon then gains 25 temporary hit points by absorbing a portion of the radiant energy.
Change Shape. The dragon 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 a bonus action to end it.
Psychic Step. The dragon magically teleports to an unoccupied space it can see within 60 feet of it.
Claw. The dragon makes one Claw attack.
Psionics (Costs 2 Actions). The dragon uses Psychic Step or Spellcasting.
Starlight Strike (Costs 3 Actions). The dragon releases a searing beam of starlight at a creature that it can see within 60 feet of it. The target must succeed on a DC 19 Dexterity saving throw or take 38 (11d6) radiant damage.
Fizban's Treasury of Dragons, p. 170