Ooldur (5e Creature)

Medium humanoid (ooldur), neutral good

Armor Class 11
Hit Points 9 (2d8)
Speed 30 ft.

Saving Throws Int +5
Skills Arcana +5, Stealth +3
Proficiency Bonus +2
Damage Vulnerabilities psychic
Senses darkvision 120 ft., passive Perception 12
Languages Undercommon, telepathy 60 ft.
Challenge 1/8 (25 XP)

Innate Spellcasting (Psionics). The ooldur's innate spellcasting ability is Intelligence (spell save DC 13). It can innately cast the following spells, requiring no components:

At will: detect thoughts
1/day each: charm person, invisibility

Psychic Susceptibility. If the ooldur takes psychic damage, it must succeed on a Intelligence saving throw with a DC of 10 or the damage taken (whichever is higher) or be stunned for 1 minute. The ooldur can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

The psychic ooldurs hide away in the deepest recesses of the Underdark. An ooldur's body is frail, but their oversized heads contain their equally massive brains, which they cover at all times with helmets they make themselves from hide and metal. An ooldur's smooth skin is grey or pale blue, their large eyes are pure black and they have little to no body hair. An ooldur's mouth, nose and ears are incredibly small and they are shorter than most other humanoids.
Ooldurs claim a hidden cavern as a home and build huts from the materials they have available. Ooldur huts are built in circles around fire pits, which the ooldurs use to cook the fungus they grow or any small creatures they're able to catch. The ooldurs line the outskirts of their home with traps to ward off any intruders. While they often expect their traps to only catch the evil inhabitants of the Underdark, if they find that they've caught an innocent they're incredibly apologetic and offer any aid they can before sending them on their way, but they rarely bring any outsiders to the main cavern.
The ooldurs desperately search for any means they can to avoid the relentless pursuit of their former masters, the dreaded mind flayers, who created them to serve a role akin to cattle and hunt them to recapture them. Mind flayers find the brains of ooldurs exquisitely delicious and consider them a delicacy. Drow and duergar avoid them, as they know keeping ooldur slaves draws the attention of the illithids, who will launch raids to reclaim the ooldurs.

Strained Psychics. While ooldurs possess telepathy and psychic abilities, they rarely use them as doing so causes immense mental strain. They are also extremely vulnerable to mental attacks, which temporarily overwhelm their minds and incapacitate them. This weakness was deliberately engineered into them by the mind flayers so that they might be contained easily. It is unknown what the ancestors of the ooldurs looked like before they were captured by the mind flayers, but some speculate that they might have been humans.
When the first ooldurs were created, they were able to escape because the illithid colony was raided by gith. Gith are said to consider the ooldurs kindred spirits and help them when they can. The ooldurs also consider flumphs their allies and often live with them.
While the ooldurs aren't especially religious, their prophets speak of a place they call the Land of Fire, a promised land in which their people will forever be safe from the mind flayers. According to ooldur myth, this place is bathed in constant warmth and gentle light and is protected by serpents whose bodies are made entirely from flame.