Cosmic Symphony
Large Celestial, unaligned
Armor Class 18 (natural armor)
Hit Points 200 (16d10+112)
Speed fly +60, walk +0
Challenge 15
Saving Throws cha +9, wis +1
Skills perception +5
Damage Resistances nonmagic B/P/S attacks
Damage Immunities radiant, thunder
Condition Immunities deafened, exhaustion, grappled, paralyzed, petrified, poisoned, prone, restrained, stunned
Senses truesight 120', passive Perception 20
Languages understands all languages but can't speak
Special Abilities
Invisible. Is invisible.
Legendary Resistance (3/Day). Choose to succeed failed save.
Magic Resistance. Advantage: spell/magic effect saves.
Actions
Multiattack. Can use Universal Music then one Discordant Wave and one Slam or two Discordant Waves.
Discordant Wave. Melee or Ranged Spell Attack: +10 to hit 5 ft. or range 60/120' one target 27 (5d8+5) thunder. Target and each creature within 10 ft. of it: DC 18 Con save or become deafened until end of its next turn.
Slam. Melee Weapon Attack: +13 to hit, 5 ft., one target, 24 (3d10+8) bludgeoning damage + 22 (5d8) thunder.
Universal Music. Each creature of symphony's choice within 120' of it: DC 18 Con save or be incapacitated 1 min. Creature that fails save by 5+ is stunned 1 min instead. Stunned or incapacitated creature can re-save at end of each of its turns success ends effect on itself. If creature's save is successful or effect ends creature is immune to symphony's Universal Music for next 24 hrs.
Celestial Crescendo (Recharge 5-6). Sound waves explode from it. Each creature within 30' of it: 45 (10d8) thunder and is deafened for 1 min (DC 18 Con half damage not deafened). A creature can re-save at end of each of its turns success ends effect on itself.
Legendary Actions
Fly. Flies up to half its flying speed with o provoking opportunity attacks.
Major Chord (2). The symphony regains 18 (4d8) hp.
Minor Chord (2). Each creature within 10 ft. of the symphony must make DC 18 Con save or take 9 (2d8) thunder.
Source: Tome of Beasts 3 · OGL/Open