Neothelids

These horrors, hated by Illithid, sometimes come into being when those ignorant of illithid lore destroy a colony. A neothelid arises when a tadpole pool is left untended. The tadpoles turn against each other, and the survivor grows to immense size.
A slime-covered worm of immense size, a neothelid is the result of the mind flayer reproductive cycle gone horribly wrong. On rare occasions, an illithid colony collapses, typically after an external assault, and the elder brain is killed. When that happens, the colony's tadpoles are suddenly freed from their fate. They no longer serve as food, and in turn are no longer fed by their caretakers. Driven by hunger, they turn to devouring one another. Only one tadpole survives out of the thousands in the colony's pool, and it emerges as a neothelid.

Basic Information

Dietary Needs and Habits

As a feral thing, a neothelid knows nothing beyond the predatory existence it has lived so far and struggles to comprehend its new psionic abilities. Neothelids prowl subterranean passages in search of more brains to sate their constant hunger, growing ever more vicious. These creatures can spray tissue-dissolving enzymes from their tentacle ducts, reducing victims to a puddle of slime and leaving only the pulsing brain unharmed. They have no knowledge of their link to illithids, so they're just as likely to prey on mind flayers as on anything else.

Additional Information

Geographic Origin and Distribution

They are native to underground caves in Glyth.

Civilization and Culture

History

Long ago, neothelids were the natural form of Illithid. The first illithid resulted when a few unwary Fraal made the mistake of stumbling upon a tadpole pool.

Interspecies Relations and Assumptions

Among the strongest taboos in illithid society is the idea of allowing a mature tadpole to survive without implanting it into a donor brain. Under normal circumstances, any tadpole that grows larger than a few inches in length is killed by the elder brain to be food for it or for less mature tadpoles. Any tadpole that survives beyond that state is perceived as a threat to the colony, and the mind flayers organize hunting parties to exterminate the abomination. Lacking enough intelligence to be detected by an elder brain's power to sense thoughts, neothelids warrant such precautions.

Genetic Descendants

• Illithid

Neothelid

Gargantuan aberration, chaotic evil

Armor Class 16 (natural armor}

Hit Points 325 21d20+105

Speed 30ft

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STR

27 +8

DEX

7 -2

CON

21 +5

INT

3 -4

WIS

16 +3

CHA

12 +1

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Saving Throws Int +1, Wis +8, Cha +6

Senses blindsight 120 ft., passive Perception 13

Languages None

Challenge 13

Creature Sense. The neothelid is aware of the presence of creatures within 1 mile of it that have an Intelligence score of 4 or higher. It knows the distance and direction to each creature, as well as each creature's Intelligence score, but can't sense anything else about it. A creature protected by a mind blank spell, a nondetection spell, or similar magic can't be perceived in this manner.
Innate Spellcasting (Psionics). The neothelid's innate spellcasting ability is Wisdom (spell save DC 16). It can innately cast the following spells, requiring no components:
At will: levitate
1/day each: confusion, feeblemind, telekinesis
Magic Resistance. The neothelid has advantage on saving throws against spells and other magical effects.

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Actions

Tentacles. Melee Weapon Attack: +13 to hit, reach 15 ft., one target. Hit: 21 (3d8 + 8) bludgeoning damage plus 13 (3d8) psychic damage. If the target is a Large or smaller creature, it must succeed on a DC 18 Strength saving throw or be swallowed by the neothelid. A swallowed creature is blinded and restrained, it has total cover against attacks and other effects outside the neothelid, and it takes 35 (10d6) acid damage at the start of each of the neothelid's turns.
If the neothelid takes 30 damage or more on a single turn from a creature inside it, the neothelid must succeed on a DC 18 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone in a space within 10 feet of the neothelid. If the neothelid dies, a swallowed creature is no longer restrained by it and can escape from the corpse by using 20 feet of movement, exiting prone.
Acid Breath (Recharge 5-6). The neothelid exhales acid in a 60- foot cone. Each creature in that area must make a DC 18 Dexterity saving throw, taking 35 (10d6) acid damage on a failed save, or half as much damage on a successful one.