Huge humanoid, beast, aberration, neutral evil
Armor Class: 19
Hit Points: 536
Speed:
40 ft
, fly: 80 ft
, can hover
Saving Throws: DEX +6, CON +11, INT +9, WIS +10
Skills: Multiattack. The dragon can use its Frightful Presence. It then makes three attacks: one with its bite and two with its claws.
Bite. Melee Weapon Attack: +11 to hit, reach 10 ft., one target. Hit: 17 (2d10 + 6) piercing damage plus 4 (1d8) acid damage.
Claw. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) slashing damage.
Maddening Presence. Each creature of the dragon's choice that is within 120 feet of the dragon and aware of it must succeed on a DC 16 Wisdom saving throw or become mad (D100 for effects, short-term madness effects can be found in dungeon masters guide) 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.
Roar (3/Day). The Fionnuala emits a magical roar. Each time it roars before finishing a long rest, the roar is louder and the effect is different, as detailed below. Each creature within 500 feet of the sphinx and able to hear the roar must make a saving throw.
First Roar. Each creature that fails a DC 18 Wisdom saving throw is frightened for 1 minute. A frightened creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
Second Roar. Each creature that fails a DC 18 Wisdom saving throw is deafened and frightened for 1 minute. A frightened creature is paralyzed and can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
Third Roar. Each creature makes a DC 18 Constitution saving throw. On a failed save, a creature takes 44 (8d10) thunder damage and is knocked prone. On a successful save, the creature takes half as much damage and isn't knocked prone.
Damage Vulnerabilities: Fire
Damage Immunities: Psychic; Bludgeoning, Piercing, and Slashing from Nonmagical Attacks
Condition Immunities: Curse of the Abyss, Charmed
Senses: Magic Weapons. The sphinx's weapon attacks are magical.
Languages: Deep Speech
Challenge Rating: 24