Illithocyte were illithid tadpoles that survived the fall of a mind flayer empire, and evolved into a new life form. They crawled about in groups seeking psychic radiation on which to feed.
Following the demise of the city of Ch'Chitl, illithocytes appeared in the surrounding areas of the Underdark as a consequence of the death of the city's elder brain.
- ↑ 1.0 1.1 1.2 1.3 1.4 Kevin Baase, Eric Jansing, Oliver Frank, and Bill Halliar (November 2005). “Monsters of the Mind – Minions of the Mindflayers”. In Erik Mona ed. Dragon #337 (Paizo Publishing, LLC), pp. 27–28.