Ancient Prismatic Dragon (5e Creature)
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Ancient Prismatic Dragon
Titanic dragon, neutral
Saving Throws Dex +12, Con +21, Wis +14, Cha +22
Legendary Resistance (3/Day). If the dragon fails a saving throw, it can choose to succeed instead.
Light Immunity. The dragon is immune to light-based spells and effects such as prismatic spray.
Siege Monster. The dragon deals double damage to objects and structures.
Multiattack. The dragon can use its Frightful Presence. It then makes one bite attack and two claw attacks. It may use its Crush or Swallow in place of its bite.
Bite. Melee Weapon Attack: +20 to hit, reach 20 ft., one target. Hit: 32 (4d10 + 10) piercing damage plus 21 (6d6) radiant damage. If the target is a creature, it is grappled (escape DC 20). Until this grapple ends, the target is restrained, and the dragon can't bite another target.
Claw. Melee Weapon Attack: +20 to hit, reach 15 ft., one target. Hit: 24 (4d6 + 10) slashing damage.
Crush. The dragon attempts to crush its foes underneath it using its weight. All creatures in the dragon's space must make a DC 28 Dexterity saving throw. On a success, a creature is not crushed, and moves out of the dragon's space to a space adjacent to the dragon. On a failure, a creature becomes grappled by the dragon (escape DC 20). While grappled in this manner, a creature is also considered prone and restrained, and takes 28 (4d8 + 10) bludgeoning damage at the start of each of the dragon's turns. A creature is freed from this grapple when the dragon moves.
Swallow. The dragon makes one bite attack against a Gargantuan or smaller creature it is grappling. If the attack hits, the target takes the bite's damage, the target is swallowed, and the grapple ends. While swallowed, the creature is blinded and restrained, it has total cover against attacks and other effects outside the dragon, and it takes 81 (18d8) acid damage at the start of each of the dragon's turns.
Frightful 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 28 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.
Prismatic Breath (Recharge 5-6). The dragon exhales prismatic energy in a 120-foot cone, which manifests as eight multicolored rays of light. Each ray is a different color and has a different power and purpose. Each creature in the area of effect must make a DC 28 Dexterity saving throw, and each creature also rolls a d8 to see which color ray affects them:
Bloodied Breath. When the dragon falls below half its hit point maximum, it uses its prismatic breath. The dragon does not need to have its prismatic breath charged, and using its breath in this manner does not consume its charge. Once the dragon uses this reaction, it can't use it again until it reaches its hit point maximum.
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.
Detect. The dragon makes a Wisdom (Perception) check.