Cosmic Symphony

Large celestial, unaligned

Armor Class 18 (natural armor)
Hit Points 200 (16d10 + 112)
Speed 0 ft., fly 60 ft. (hover)

19 (+4) 26 (+8) 25 (+7) 2 (–4) 21 (+5) 18 (+4)

Saving Throws Wis +10, Cha +9
Skills Perception +10
Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks
Damage Immunities radiant, thunder
Condition Immunities deafened, exhaustion, grappled, paralyzed, petrified, poisoned, prone, restrained, stunned
Senses truesight 120 ft., passive Perception 20
Languages understands all languages but can’t speak
Challenge 15 (13,000 XP)
Proficiency Bonus +5


  • Invisible. The cosmic symphony is invisible.
  • Legendary Resistance (3/Day). If the cosmic symphony fails a saving throw, it can choose to succeed instead.
  • Magic Resistance. The cosmic symphony has advantage on saving throws against spells and other magical effects.


  • Multiattack. The cosmic symphony can use Universal Music. It then makes one Discordant Wave attack and one Slam attack or two Discordant Wave attacks.
  • Discordant Wave. Melee or Ranged Spell Attack: +10 to hit, reach 5 ft. or range 60/120 ft., one target. Hit: 27 (5d8 + 5) thunder damage. The target and each creature within 10 feet of it must succeed on a DC 18 Constitution saving throw or become deafened until the end of its next turn.
  • Slam. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 24 (3d10 + 8) bludgeoning damage plus 22 (5d8) thunder damage.
  • Universal Music. Each creature of the symphony’s choice within 120 feet of the cosmic symphony must succeed on a DC 18 Constitution saving throw or be incapacitated for 1 minute. A creature that fails the saving throw by 5 or more is stunned for 1 minute instead. A stunned or incapacitated 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 cosmic symphony’s Universal Music for the next 24 hours.
  • Celestial Crescendo (Recharge 5–6). Sound waves explode from the cosmic symphony. Each creature within 30 feet of the symphony must make a Constitution saving throw. On a failure, a creature takes 45 (10d8) thunder damage and is deafened for 1 minute. On a success, a creature takes half the damage and isn’t deafened. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.


The cosmic symphony can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature’s turn. The cosmic symphony regains spent legendary actions at the start of its turn.

  • Fly. The cosmic symphony flies up to half its flying speed without provoking opportunity attacks.
  • Major Chord (Costs 2 Actions). The symphony regains 18 (4d8) hp.
  • Minor Chord (Costs 2 Actions). Each creature within 10 feet of the symphony must succeed on a DC 18 Constitution saving throw or take 9 (2d8) thunder damage.


Humming reverberates through the air as spinning rings of rainbow light shimmer in the sky.

A cosmic symphony is invisible, being made of heavenly sound, but those capable of seeing invisible creatures see an angelic being shimmering with rainbow-colored light.

Music of the Spheres. Cosmic symphonies form only when a remarkable event upsets the predestined rhythms of the universe. This upset reverberates as a living symphony that exists for as long as it takes to play through its unique musical movements.

Soul Music. The music emitted by the cosmic symphony is felt rather than heard. Any creature with a soul can perceive the symphony’s music, regardless of if it can normally hear sound. Consequently, the majority of fiends and celestials are unable to hear the symphony.

Section 15: Copyright Notice

Tome of Beasts 3 © 2022 Open Design LLC; Authors: Eytan Bernstein, Celeste Conowitch, Benjamin L. Eastman, Robert Fairbanks, Scott Gable, Basheer Ghouse, Richard Green, Jeremy Hochhalter, Jeff Lee, Christopher Lockey, Sarah Madsen, Ben Mcfarland, Jonathan Miley, Kelly Pawlik, Sebastian Rombach, Chelsea Steverson, Brian Suskind, Mike Welham

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