Umbral Coil of the Veiled Abyss

In the dim light of forgotten caves and the shadowy corners of ancient ruins slumbers a creature formed from pure darkness. It resembles an enormous serpentine entity, its body shimmering with a textured sheen that pulsates like the ebbing tide of an otherworldly sea. Eyeless but ever-aware, it glides silently, leaving a trace of coldness in its wake. With its unique ability to consume not just the light around it but also the very thoughts of the living, it ensnares adventurers in a web of fear and despair, turning their own memories into weapons against them. Those who face it feel their resolve waning, thoughts scattered, and hope dimmed, as this shrouded terror seeks to devour their essence.


Medium aberration, chaotic neutral

Armor Class 15 (natural armor)
Hit Points 112 (15d8 + 45)
Speed 30 ft., climb 30 ft., swim 30 ft.

STR DEX CON INT WIS CHA
16 (+3) 18 (+4) 16 (+3) 12 (+1) 14 (+2) 10 (+0)

Saving Throws Dex +7, Con +6, Wis +5
Skills Stealth +10, Perception +5, Insight +5
Damage Resistances Psychic; Bludgeoning, Piercing, and Slashing from Nonmagical Attacks
Condition Immunities Blinded, Charmed, Deafened, Frightened
Senses Blindsight 60 ft. (blind beyond this radius), Passive Perception 15
Languages Understands Deep Speech but cannot speak
Challenge 7 (2,900 XP)
Proficiency Bonus +3

Amorphous. The creature can move through a space as narrow as 1 inch wide without squeezing.

Consume Memory. When a creature starts its turn within 30 feet of it and can see its shimmering form, it must succeed on a DC 15 Wisdom saving throw or lose one memory of its choice (randomly determined by the DM). The loss of a memory has no mechanical effects, but it causes the creature to have disadvantage on its next ability check or attack roll as it struggles to recall what was lost.

Shadow Stealth. While in dim light or darkness, the creature can take the Hide action as a bonus action.

Actions

Multiattack. The creature makes two attacks: one with its Bite and one with its Memory Drain.

Bite. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 15 (2d10 + 4) piercing damage.

Memory Drain. Melee Spell Attack: +6 to hit, reach 15 ft., one creature. Hit: 22 (4d10) psychic damage, and the target must succeed on a DC 15 Intelligence saving throw or have disadvantage on all rolls until the end of its next turn as it grapples with unsettling thoughts and fading memories.

Void Leap (Recharge 5-6). The creature can teleport up to 60 feet to an unoccupied space in dim light or darkness that it can see. After doing so, each creature within 15 feet of the destination must succeed on a DC 15 Dexterity saving throw or take 11 (2d10) psychic damage and be frightened until the end of its next turn.


This creature can serve as a formidable foe for mid-level adventurers, weaving terror and confusion into the very fabric of the encounter while offering opportunities for clever players to uncover its weaknesses and exploit them in the shadows of their own strategy.