monster

Specter of the Sunken King

CR 20

Medium undead, Lawful Evil

Reveal Stat Block

Armor Class

Hit Points

325 (30d8 + 150)

Speed

0 ft., fly 60 ft. (hover)

str

dex

con

int

wis

cha

Saving Throws CON +11, INT +12, WIS +13, CHA +15

Damage Resistances acid, fire, lightning, thunder; bludgeoning, piercing, and slashing from nonmagical attacks

Damage Immunities cold, necrotic, poison

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

Senses truesight 120 ft., passive Perception 19

Languages Common, Ancient Argentari

Traits

Legendary Resistance (3/Day).If the Specter fails a saving throw, it can choose to succeed instead.

Incorporeal Movement.The Specter can move through other creatures and objects as if they were difficult terrain. It takes 5 (1d10) force damage if it ends its turn inside an object.

Aura of the Sunken Empire.The area within 60 feet of the Specter is filled with spectral sea water. Creatures without a swimming speed treat this area as difficult terrain. Additionally, any creature that starts its turn in the aura must succeed on a DC 20 Constitution saving throw or begin to drown (see PHB rules for suffocating).

Actions

Multiattack.The Specter makes three Drowning Touch attacks. It can replace one attack with a use of its Command of the Sunken Court.

Drowning Touch.Melee Spell Attack: +15 to hit, reach 10 ft., one target. Hit: 32 (5d10 + 5) necrotic damage plus 22 (4d10) cold damage. The target must succeed on a DC 22 Constitution saving throw or its hit point maximum is reduced by an amount equal to the necrotic damage taken.

Command of the Sunken Court (1/Day).The Specter summons 2d6 'Skeleton Crew' members or 1d4 'Wraiths' in unoccupied spaces within 60 feet. The summoned creatures act as allies and remain for 1 hour or until they are destroyed.

Regal Decree of Death (Recharge 5-6).The Specter points at a creature it can see within 120 feet. The target must make a DC 22 Wisdom saving throw. On a failure, the creature takes 77 (22d6) psychic damage and is paralyzed by the weight of its own sins for 1 minute. On a success, the creature takes half as much damage and is not paralyzed.

Legendary Actions

Scepter Swipe.The Specter makes one Drowning Touch attack.

Tidal Wave (Costs 2 Actions).The Specter conjures a spectral wave in a 60-foot line that is 15 feet wide. Each creature in that line must succeed on a DC 22 Strength saving throw or be pushed 40 feet away and knocked prone.

Rise of the Sunken King (Costs 3 Actions).The Specter regains 30 hit points as it absorbs the life force of the surrounding environment. Any living creature within 30 feet takes 14 (4d6) necrotic damage.

Specter of the Sunken King

This spectral entity is the lingering consciousness of a forgotten monarch from the Argentari Sunken Empire. Draped in tattered, waterlogged finery and wearing a crown of rusted coral, the Specter haunts the flooded ruins of his former glory. He is no longer a simple ghost; he is an Epic Undead whose presence warps the very environment, bringing the crushing pressure and freezing cold of the deep ocean into the material plane.

The Specter is obsessed with the "reclamation" of his kingdom, viewing any living creature that enters his domain as a subject to be judged—and inevitably condemned to join his silent, sunken court. He possesses a terrifying, cold intellect and commands the spirits of his long-dead subjects with absolute authority.

Secret Motivation: The Specter is bound to a specific "Regal Seal" lost in the silt of the Sunken Bastion. He cannot rest until the seal is returned to his throne, but he intends to use the seal to anchor his spectral kingdom permanently to the material world, drowning the coastal regions to expand his empire.

Adventure Hook: Divers exploring the Boiling Coast have triggered an ancient mechanism, causing the Specter to manifest in full power. Coastal cities are being flooded by "impossible tides," and the local wells are turning into salt water. The party must descend into the Sunken Bastion to defeat the King before he completes his ritual of reclamation.