Star Spawn Larva Mage

Star Spawn Larva Mage CR: 16

Medium aberration, chaotic evil

Armor Class: 16 (natural armour)

Hit Points: 168 16d8+96

Speed: 30 ft

STR

17 +3

DEX

12 +1

CON

23 +6

INT

18 +4

WIS

12 +1

CHA

16 +3

Saving Throws: Dex +6, Wis +6, Cha +8

Skills: Perception +4

Damage Resistances: Cold, Bludgeoning, Piercing and Slashing from nonmagical weapons.

Damage Immunities: Psychic

Condition Immunities: Charmed, Frightened, Paralysed, Petrified, Poisoned, Restrained.

Senses: Darkvision 60 ft, passive Perception 16

Languages: Deep Speech

Challenge Rating: 16

Innate Spellcasting. The larva mage's innate spellcasting is Charisma (spell save DC 16, +8 to hit with spell attacks). It can innately cast the following spells, requiring no material components.

At will: Eldritch Blast (3 beams, +3 bonus to each damage roll), Minor Illusion

1/day: Circle of Death

3/day: Dominate Monster.

Return To Worms. When the larval mage is reduced to 0 hit points, it breaks apart into a swarm if insects in the same space. Unless the swarm is destroyed, the larva mage reforms from it 24 hours later.

Actions

Slam. Melee Weapon Attack +8 to hit, reach 10 ft, one target. Hit 7 1d8+3 bludgeoning damage, and the target must succeed on a DC 19 Constitution saving throw or be poisoned until the end of it's next turn.
Plague of Worms (Recharge 6). Each creature other than a star spawn within 10 feet of the larva mage must succeed on a DC 19 Dexterity saving throw or take 22 5d8 necrotic damage and blinded & restrained by masses of swarming worms. The affected creature takes 22 5d8 necrotic damage at the start of each of the larval mage's turns. The creature can repeat the saving throw at the end of each of it's turns, ending the effect on itself on a success.

Reactions

Feed on Weakness. When a creature within 20 feet of the larva mage fails a saving throw, the larva mage gains 10 temporary hit points.

Legendary Actions

The larva magic 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 larva mage regains spent legendary actions at the start of it's turns.
Cantrip (Costs 2 Actions). The larva mage casts one cantrip.
Slam (Costs 2 Actions). The larva mage makes one slam attack.
Feed (Costs 3 Actions). Each creature restrained by the larva mage's Plague of Worms takes 13 3d8 necrotic damage, and the larva mage gains 6 temporary hit points.

Star spawn larva mages are abominations of a mortal body and otherworldly substance. When a powerful cultist makes contact with a wormlike entity (usually a warlock,  another spellcaster sometimes, or an occultist), their mind is scrubbed of all consciousness and filled with a portion of the entity. At this time the previous person is all but destroyed, and their body mutates, creating an image of the person they were, but either made of some strange mutable material. This material can be transformed to worms, or bear wormlike appearances when it wants to.

Related Organizations

• The Church Under The Sea