Dragon, Prismatic Ancient

Gargantuan Dragon, neutral. CR 21, AC 20, 407 HP. Traits: Legendary Resistance.

Armor class
20
Hit points
407
Challenge
21
Creature type
Dragon
Size
Gargantuan
Alignment
neutral
Legendary
Yes

Stat block

Cha
19
Con
27
Dex
10
Int
20
Str
25
Wis
17
Speed
Walk: 50; Climb: 40
Senses
blindsight 60', darkvision 120', passive Perception 27
Skills
Perception: 3
Actions
  • Multiattack. Uses Frightful Presence then one Bite and two Claws.
  • Bite. Melee Weapon Attack: +14 to hit, 15 ft., one target, 18 (2d10+7) piercing damage.
  • Claw. Melee Weapon Attack: +14 to hit, 10 ft., one target, 14 (2d6+7) slashing damage.
  • Tail. Melee Weapon Attack: +14 to hit, 20 ft., one target, 16 (2d8+7) bludgeoning damage.
  • Frightful Presence. All it picks within 120' and aware of it frightened 1 min (DC 19 Wis negates) Can re-save at end of each of its turns. Save/effect ends: immune 24 hrs.
  • Breath Weapon (Recharge 5-6). Uses one of the following:Light Beam. Emits beam of white light in a 120' line that is 10 ft. wide. Each creature in line: 90 (20d8) radiant (DC 23 Dex half).Rainbow Blast. Emits multicolored light in 90' cone. Each creature in area: 72 (16d8) damage (DC 23 Dex half). Dragon splits damage among acid cold fire lightning or poison choosing a number of d8s for each type totaling 16d8. Must choose at least two types.
  • Spellcasting. Int (DC 20) no material components: At will: charm person dancing lights prismatic spray1/day: prismatic wall
Languages
Common, Draconic
Saving throws
Wisdom: 1; Charisma: 1; Dexterity: 7; Constitution: 1
Damage immunities
radiant
Legendary actions
  • Detect. Makes a Wis (Perception) check.
  • Tail Attack. Makes a tail attack.
  • Cast a Spell (2). Uses Spellcasting.
  • Shimmering Wings (2). Each creature within 20': DC 19 Wis save or take 16 (3d10) radiant and blinded until start of its next turn.
Special abilities
  • Legendary Resistance (3/Day). Choose to succeed failed save.
Condition immunities
blinded

Source and licence

From Tome of Beasts 3 (open content).

Licence: Open Game Content (OGL 1.0a).

Every licence notice Tavern Bag relies on.