Ailinoth

Amphibious. Ailinoth can breathe air and water.

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

Radiant Glory. All of Ailinoth's attacks deal an extra 22(5d8) radiant damage (included in attack)

Spellcasting. Ailinoth is an 20th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 27, +19 to hit with spell attacks). Ailinoth has the following Sorcerer spells prepared:

Cantrips (at will): mage hand, prestidigitation, light

1st level (4 slots): detect magic, sleep, shield, thunderwave

2nd level (3 slots): acid arrow, detect thoughts, invisibility, silent image

3rd level (3 slots): counterspell, dispel magic, Haste, Clairvoyance

4th level (3 slots): confusion, banishment

5th level (3 slots): animate objects, teleportation circle

6th level (2 slot): eyebite, globe of invulnerability

7th level (2 slot): plane shift, teleport

8th level (1 slot): dominate monster, power word stun

9th level (1 slot): Time Stop

Multiattack. Ailinoth can use her Frightful Presence. It then makes three attacks: one with its bite and two with its claws.

Bite. Melee Weapon Attack: +19 to hit, reach 15 ft., one target. Hit: 26 (3d10 + 10) piercing damage and an additional 22(5d8) radiant damage.

Claw. Melee Weapon Attack: +19 to hit, reach 10 ft., one target. Hit: 20 (3d6 + 10) slashing damage and an additional 22(5d8) radiant damage.

Tail. Melee Weapon Attack: +19 to hit, reach 20 ft., one target. Hit: 19 (3d8 + 10) bludgeoning damage and an additional 22(5d8) radiant damage.

Frightful Presence. Each creature of Ailinoth's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 24 Wisdom 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 dragon's Frightful Presence for the next 24 hours.

Breath Weapons (Recharge 5–6). Ailinoth uses one of the following breath weapons.

Fire Breath. Ailinoth exhales fire in a 90-foot cone. Each creature in that area must make a DC 24 Dexterity saving throw, taking 88 (16d10) fire damage on a failed save, or half as much damage on a successful one.

Weakening Breath. Ailinoth exhales gas in a 90-foot cone. Each creature in that area must succeed on a DC 24 Strength saving throw or have disadvantage on Strength-based attack rolls, Strength checks, and Strength saving throws 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.

Change Shape. Ailinoth magically polymorphs into a humanoid or beast that has a challenge rating no higher than its own, or back into its true form. It reverts to its true form if it dies. Any equipment it is wearing or carrying is absorbed or borne by the new form (Ailinoth's choice).

In a new form, the dragon retains its alignment, hit points, Hit Dice, ability to speak, proficiencies, Legendary Resistance, lair actions, and Intelligence, Wisdom, and Charisma scores, as well as this action. Its statistics and capabilities are otherwise replaced by those of the new form, except any class features or legendary actions of that form.

The dragon 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. The dragon regains spent legendary actions at the start of its turn.

Quickspell. Ailinoth casts a spell of 5th level or lower.

Tail Attack. Ailinoth makes a tail attack.

Wing Attack (Costs 2 Actions). Ailinoth beats its wings. Each creature within 15 feet of Ailinoth must succeed on a DC 27 Dexterity saving throw or take 20 (3d6 + 10) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.