Zataalehoth Worms Of The Grasping Goddess

“He went on about monsters, sleeping in great caverns underground and especially under the sea, waiting for a chance to take over the surface world.”

Small

No. Enc.: 1d8

Alignment: Neutral 

Move: 120'(40’)

Armor Class: 9

Hit Dice: 1

Attacks: 1

Damage: 1d4 (plus special)

Morale: 4

These creatures are often found within the remains of crypts & other loathsome places Suppressed church records state that the tombs often  contained 'that which is too horrible and vile to describe'. Among  the remains of bodies of worshipers of foul & dangerous beings are these small worms. These worms are often the final piece in the jig saw puzzle of the rites of lichdom. These creatures are not "magical" in nature but rather genetically engineered life forms that live within their hosts. These foul things become a part of the psychic energy pools during the rites & their by increasing their hosts psi point pools enabling the host to take on far more power then they should be able to in life. Their bodies reduced to shriveled husks with which they manage to maintain inhuman mobility and active thought. 

The creature allows the foul undead thing to continue to function even when the body would normally sleep. The worm like thing can even animate the bodies of some alien beings through arcane rites when the body or corpse should be completely decayed. The worm retains the psychic life essence & can communicate with the living through these complex rites often involving a copper knife, the communication gear of the Mi-go, & the jellies of space angels.
They can release a psychic blast of energy twice a day doing 1d8 points of damage unless a save vs is made. 

Bierce describes liches thus:

"For by death is wrought greater change than hath been shown. Whereas in general the spirit that removed cometh back upon occasion, and is sometimes seen of those in flesh (appearing in the form of the body it bore) yet it hath happened that the veritable body without the spirit hath walked. And it is attested of those encountering who have lived to speak thereon that a lich so raised up hath no natural affection, nor remembrance thereof, but only hate. Also, it is known that some spirits which in life were benign become by death evil altogether."

These foul worms can even be transfered back to the living & retain the memories of their former hosts bestowing a faux style of immortality. These creatures are sometimes passed down from one generation to the next among certain alien races. This has lead to the legend of alien space princes & priests. These are actually depraved astronauts & scientists. 

Story inspiration here Africa mummies parasites