Neh-thalggu

Brain collectors, or neh-thalggu in their own language, were a race of creatures found across multiple planes.

Description
Neh-thalggu were about with six crab-like legs and dozens of short tentacles. They had yellow-orange skin and a bloated, almost amorphous body. The head area of the body had four eyes and a large, tooth-filled maw. Additionally, a brain collector could have up to twelve lumps on its head, which contained the brains it had collected.

Abilities
Neh-thalggu were highly intelligent, and were also capable spellcasters. The amount of spells they could cast depended on the number of brains one had collected.

Neh-thalggu spoke their own language, as well as Diabolan, the language of the diaboli. They also could speak any language spoken by someone whose brain they had taken.

Personality
Brain collectors possessed a completely alien psychology: while not exactly hostile, they did not regard humanoids as people.

Combat
In combat, neh-thalggu relied on their powerful jaws and their spellcasting ability, and displayed considerable tactical ability due to their high intellect. Interestingly, they would take great care to avoid damaging the cranium of their opponents.

Society
Neh-thalggu were solitary creature known to live on the Material plane, Astral plane, Ethereal plane, and the Demiplane of Nightmares. On the first in particular they were known to prefer ruins or caverns where there was little light and minimal disturbances. However, the homeplane of the neh-thalggu was unknown.

Brain collectors always sought to acquire brains as quickly as possible, and did so by carefully cutting off the top of the head of a slain humanoid using surgical tools, then swallowing the brain. Once one had collected twelve brains, it immediately sought to return to its home plane. According to one theory, a twelve-brain neh-thalggu could open a link to its native plane when in a certain location.

On the Demiplane of Nightmares, neh-thalggu occupied a place in diabolus legends similar to the one dragons held in human legends. Diaboli regarded neh-thalggu as creatures of great power, cunning, and inscrutability. Additionally, neh-thalggu were some of the few creatures whose magic could effect a diabolus.