Huge undead (ghost), neutral

Armor Class: 11

Hit Points: 238 ( 14d12+70 )

Speed: 0 ft , fly: 50 ft , swim: 50 ft

STR

23 +6

DEX

13 +1

CON

20 +5

INT

8 -1

WIS

11 +0

CHA

4 -3

Saving Throws: CON ( 1d20+9 ), WIS ( 1d20+5 )

Skills: Perception +9, Stealth +5

Damage Resistances: acid, fire, lightning, thunder

Damage Immunities: cold, necrotic, poison; bludgeoning, piercing, and slashing from nonmagical attacks

Condition Immunities: charmed, exhaustion, fright­ened, grappled, paralyzed, petrified, poisoned, prone, restrained

Senses: darkvision 60 ft., passive Perception 19

Languages: Druidc, Aquan

Challenge Rating: 10 (5,900 XP)

Actions

• Multiattack. Cauldronboil makes uses Horrifying Visage and then makes a Withering Bite.
• Withering Bite. Melee Weapon Attack: 1d20+10 to hit, reach 5 ft., one target. Hit: 22 ( 3d10+6 ) necrotic damage. This damage heals Cauldronboil for the same amount. If the target is a creature other than an elf or undead, it must succeed on a CON saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
• Etherealness. Cauldronboil enters the Ethereal Plane from the Material Plane or vice versa. He is visible on the Material Plane while it is in the Border Ethereal, and vice versa, yet he can't affect or be affected by anything on the other plane.
• Horrifying Visage. Each non-undead creature within 60 feet of Cauldronboil that can see him must succeed on a DC 13 Wisdom saving throw or be frightened for 1 minute. If the save fails by 5 or more, the target also ages 1d4 × 10 years. A frightened target can repeat the saving throw at the end of each of its turns, ending the frightened condition on itself on a success. If a target's saving throw is successful or the effect ends for it, the target is immune to Cauldronboil's Horrifying Visage for the next 24 hours. The aging effect can be reversed with a greater restoration spell, but only within 24 hours of it occurring.
• Starshine. Ranged Spell Attack: 1d20+10 to hit, range 120 ft., one target. Hit: 26 ( 6d6+1 ) fire damage, and the target is blinded until the start of Cauldronboil’s next turn.

Bonus Action

• At will: beast sense, entangle, speak with animals, barkskin* (attackers take 5 piercing damage each time they strike Cauldronboil)
• 3/day each: animal messenger, dominate beast, faerie fire, tree stride
• 1/day each: commune with nature (as an action), mass inflict wounds

Reactions

Outnumbered! If Cauldronboil is damaged by an attack he may move up to his swim speed and use Withering Bite or Wildfire against the triggering attacker; he then uses Etherealness.

Suggested Environments

Aquatic