You have become Goetia, Beast I. You gain all of his abilities, skills and memories. The Demon Gods are now a part of you and yours to command. You gain the Temple of Time, also known as Ars Paulina, a workshop that exists outside of the universe and outside of time, located in the space of imaginary numbers.
Each Demon God has a distinct personality, but they exist as a unified being. Through the use of Ars Paulina, they are able continuously revive no matter how many times they were fought. Killing Demon God Pillars requires destroying all 72 at once — if even one remains intact, they will resurrect their fallen members.
Their pillar forms, although varied in appearance, share a similar shape resembling a cephalopod tentacle with rings of eyes (either round or angular) in place of suckers. The colors of the pillars vary, with many having black skin and red eyes. The immense scale of the Demon God is difficult to grasp — the pupils of each pillar have diameters that are multiple times the size of a regular human, making them towering and horrifying figures. These giants are adorned with a surface layer of frozen human bodies, both young and old, beautiful and ugly, each with a distinct expression reflecting the moment of absorption: agony, pain, sadness, anger, and other emotions. This body pile is a staggering three meters deep, beneath which lie the actual muscles and blood vessels of the Demon God. Over time, as the bodies are assimilated and absorbed, they become covered in a blanket of deep red lines. Once these lines appear, the bodies will eventually break down, creating more "blood" for the Demon God.
The destruction of Ars Paulina will undo the union of the immortal colony of the 72, causing them to become individual Demons and preventing them from reviving their fallen numbers. The only way to destroy Ars Paulina is through your death or the use of the Noble Phantasm: Ars Nova.