One of the more interesting and less-developed races in Spelljammer were the stout grav, a race of miners who are able to manipulate gravity. The material presented for them makes no actual mention of a deity or faith that they follow or even priests, but it typically strikes me as unusual when races have no deities in D&D. Since the grav have featured heavily in the current leg of my Spelljammer campaign, it gave me ample opportunity to work on their culture and faith, and so I created the deity Kavor for them. Included with the PDF is the writeup for gravs as a PC or NPC race that I created as well.
The second of the Derro Twins, banished from the Morndinsamman for their crimes, is Diinkarazan, the Mad God. Betrayed by his brother and imprisoned by Ilsensine, he has been driven mad by the hallucinations inflicted by the mind flayer god. However, he gains lucidity periodically, but not for long enough to effect his freedom.
A minor, nearly forgotten member of the Seldarine, Alathrian Druanna is the goddess of writing, subservient to Labelas Enoreth in his role as keeper of history. Because of her portfolio on writing, she has come to hold the fields of conjuration, geometric, and runic magic as well, although only a small number of elves still follow her tenets.
Cador is virtually unknown dwarven deity of revenge and hatred, not truly part of the Morndinsamman, but also acting as a dark reflection of the pantheon as a whole. He only shows up in a single 1st Edition adventure, Nigel Findley’s “Caermor” from Dungeon #2 (and reprinted in 2nd Edition’s Dungeon anthology release, “Dungeons of Despair”). I expanded upon the slight details there to make Cador a full-fledged deity.
Diirinka is the treacherous and cruel patron of the degenerate dwarves known as derro. Exiled from the Morndinsamman for his crimes against his brother and mortal dwarves, he hides in Pandemonium, paranoid that his enemies, especially the illithid god Ilsensine, will find and destroy him. Diirinka is interesting because he doesn’t have a traditional priesthood, and has special wizard-like characters called Savants instead. I took this opportunity to “formalize” the Savants into a type of Specialty Priest, but without priest spell access; I tried to match the basic and somewhat randomized way the savants operate in the Derro Monstrous Compendium entry.