Neothelids were extremely rare creatures in mind flayer society.


To create a neothelid, not only must an illithid tadpole not undergo ceremorphosis, but the elder brain of the colony must have died, as the elder brain would normally eat all tadpoles that failed to undergo ceremorphosis. With the elder brain dead, chaos would erupt in the spawning pools, as the society around them collapsed as well. If one tadpole survived the resulting chaos, it could grow into the form of a gigantic slug-like creature.[3] The process wasn't an instant one. A would-be neothelid was a feral monster until it ate a sentient creature. Eating such a being gave it self-awareness and its psionic powers.[4]


One of these creatures took up residence in the old illithid colony of Phanlinksal.[3]



  1. 1.0 1.1 Wizards RPG Team (2016). Volo's Guide to Monsters. (Wizards of the Coast), p. 181. ISBN 978-0786966011.
  2. 2.0 2.1 2.2 Bruce R. Cordell (1998). The Illithiad. (TSR, Inc), p. 95. ISBN 0-7869-1206-5.
  3. 3.0 3.1 Eric L. Boyd (1999). Drizzt Do'Urden's Guide to the Underdark. (TSR, Inc), pp. 22, 43. ISBN 0-7869-1509-9.
  4. Richard Baker, James Jacobs, and Steve Winter (April 2005). Lords of Madness: The Book of Aberrations. (Wizards of the Coast), p. 67. ISBN 0-7869-3657-6.