The forging of Angel Bodies.
After the First Conquest came the golden age of the Demiurges. Many great works were performed by the demiurges including forging new armour for the Angels. The new law was also laid down and those Protectors who accepted the new armored bodies took up their role again to protect Throne.
Pericloss seems to be one those Craftsmen who devised the crafting of new Angel bodies. Highly skilled in craft, and with a clear understanding of the enduring, steadfast nature of Angels. Pericloss nevertheless felt the need to issue a warning.
Little has been revealed of the crafting of Angel armor though this quote survives.