Carl Lynwood Sargent
Carl Lynwood Sargent (1952-2018) was the real-life 1970s-era Doctor Peter Venkman, complete with the "parapsychology" Ph.D., except British. Like Venkman he got BTFOed from that profession; unlike Venkman, he tried his hand at real fantasy instead. At that, it depends whom you ask.
Credits include co-writing Gazetteer 13, The Shadow Elves; Iuz the METALEvil for Greyhawk; Night Below for Greyhawk but barely abstracted away. He was going to do a supplement for The Great Kingdom in Greyhawk too but TSR slipped on a pile of Lorraine Williams' own turds before that could happen. This material ended up in Dragon #204, 206, 208.
Sargent's D&D work features psionics, madness, and underworld elves what ain't drow. He also likes to build evil cities for PCs to infiltrate. In the annals of D&D skub, Carl Sargent's greatest effect - we cannot quite say "contribution" - was upon Second-Edition Greyhawk in WGS1: Five Shall Be One and then From The Ashes.
Soon after Night Below, Sargent disappeared and stayed disappeared for the next two decades, apparently into Nottinghamshire in the UK. He died 12 September 2018. Meanwhile fans of his parapsychology had Bruce Cordell to feed their itch, who kept more emotional distance from the themes and also didn't fuck up canon (as bad).