1d6 Random Guardian Spirits of The Underworld Encounter Table For Your Old School Campaigns

Down in the depths of the Earth the world of the living, the dead, & the lost cross paths in the darkness. Time, space, & even reality breakdown in even measure but these are the places where even the gods fear to trod. They were not meant for mortals even heroes. But these pathways are guarded by terrible spirits of ancient times. Things fell & foul that man was not meant to cross paths with. 

Many of these beings are spirits of the underworld & have many of the characteristics of demons. They are often found guarding the treasures or relics of the gods. These spirits are often:

1. Immunity to electricity and poison. 
2. Only take a quarter damage from  fire, acid, & cold 
3. Highly telepathic, & able to speak The Black Tongue, Hyperborean high & low, most known languages 
4. Dark Vision 130' 
5. Able To Summon A Minor Demon Once Per Day 
6. Able to Polymorph three times per day 

These beings are able to be summoned by a witch with a minor summon monster spell for counsel and advice once a month. They often act as advisors & go betweens with certain underworld spirits or gods.
 

1. Caulilalrgot Cangulkoncal was once a lamia princess but elevated to the position of guardian after slaying four hundred cultists during the wasting plague years. She guards a cache of Atlantis god works deep within a captured temple of Apollo. She will hunt and kill any parties of adventurers she comes across.
2. Derc Hiaurcar 'prince of the vampire worms' is a foul being who has become a spirit guardian of the underworld after capturing a temple of the toad gods. He sacrificed all of his minions for this honor and now tracks the treasures he guards through the underworld. 
3. Baellkordulug blessed of the water lizard is a lizard man whose taken on the ancient mantle of guardian of the foul shrine of his people's Lovecraftian god thing. He is slow to anger but takes his vengeance out on any adventurers. 
4. Ninturnango is a throat worm that has become a humanoid horror in the service to his god master after possessing the husk of a mummy from Lemuria. He is now a guardian of ancient treasure from that lost country. His own spawn infect any bodies they can as foul demon throat worms.  
5.  Valalangungbe 'the walker in darkness' is a shadow demon of horrid aspect that has possessed the body of a fell prince of the Ixians. He is now the guardian of a portal to an alien hell and a treasure of lost Atlantis. Hates Hyperboreans with a burning passion. 
6. Gel Basrahuj - A Hyerpborean princess's mummy that has ascended into guardian hood of the foul treasures of her pleasure and demon lusting ancestors. She now has 1d6 demonic traits each time she awakens from slumber.