There is an edict, centuries old, which declares those who eat the deadened flesh of their own kind to be cursed - that that flesh by right belongs to the scavenger-god Yeenoghu and her priests.
The accursed wallow and groan and spread across the earth as a fevered stain. Their hunger is bottomless, but it has an apex - each tithes a portion of every mouthful of choked-down putridity to the one who changed them, and to the one who changed them in turn, all the way up the chain until the collected feast gathers in the belly of the mountainous ghoul-king, in his palace of teeth and filth.
And even the king can never be satisfied. From his palace he whispers in the dreams of malefactors and maleficarum, of this unwholesome technique:
Take a carcass which vultures have not torn and hyenas have not tasted, and lay it in a structure where crows have not alit and jackals have not tread. Whisper to it in the dark for three days and three nights, eating only fistfuls of dirt and drinking only your own tears and urine.
Should everything go properly, the ghoul-king will lend a portion of his power and a maggot will spawn within the meat, inscribed with the Unspeakable Name. This maggot will spawn more, until a great white mass rises in the shape of a man.
These larvae are not given freely, not meant to be servants - this is only a ploy.
Once one reaches maturation it will moult into a usurper of the scavenger-god, and the ghouls shall glut upon the world entire.
They are
Maggot Golems
HP: 100 + The Heart of the Swarm AC: 12 + Writhing Mass ATK: 1d8/1d8 slams, or 1d4 gnawing flood (hits all in melee range automatically) SAV: 10 MOV: As ogre, or flow as wave of maggots INT: According to orders, literal-minded ML: 12
No. Appearing: 1
The Heart of the Swarm: Maggot golems do not roll for HP with HD as normal (if HD value is needed, use 8). Each maggot golem begins with 100 HP. When a maggot golem takes a hit, it loses HP as normal, and has a percentage chance of dying immediately as its core maggot is destroyed based on how much HP it has lost (e.g. if a hit brings a maggot golem down to 67 HP it then has a 33% chance of dying immediately).
Writhing Mass: Maggot golems take the minimum possible damage from human-scale weapons (e.g. 1 on a d6), plus whatever bonus damage a weapon might get from enchantment. Area of effect attacks, siege weapons, and the like do damage as normal.
No Flesh Leaves The Abattoir: Maggot golems that come across a corpse are compelled to devour it. They must remain motionless for one round per HD of the corpse, and heal 1d6 HP per round. It may attack those within range as normal.
Also, wounds dealt by a maggot golem are prone to myiasis.