Daemonculaba
From Lexicanum
The Daemonculaba is an unusual system that permitted the Iron Warriors to create new Chaos Space Marines. The system begins with the fattening of human slaves. These captives were bound and force fed nutrients, widening their bodies to grotesque proportions. Once large enough the male slaves were skinned for their flesh, which would be used to clothing the freshly born candidates who passed inspection. The women were carried away to become part of the Daemonculaba's birthing wombs.
The enlarged female slaves were bound, their insides altered and chemistry wired by the Savage Morticians (who are possibly Chaos corrupted members of Adeptus Mechanicus' biological division), through a combination of the captured gene-seed and the use of a restrained daemon. The exact science is vague, but by taking a child and sealing him within the stomach of one of the enslaved women, the process would either transform the child into an Astartes, or mutate horribly and create an abomination. Either way, the candidate is reborn later without flesh. If it passes inspection, the new recruit is clothed in flesh carved from the male slaves. If it fails, the reject is cast out through the fortress' sewer system. Some of these rejects survive, however, and become scavenger-hunter creatures known as the Unfleshed.
