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The Almighty is the complete form of the Zero Fragment. it is described as being the closest thing to The Second one could possibly be, in effect being a God. It allows one to rewrite reality to their whims. Like the name implies it is all powerful. It has been shown to not only change someone's physical gender on the genetic level but also resurrect the dead and create new bodies for them out of nothing.
This power is obtainable by those belonging to the Adam Project only, which requires the Zero Fragment. Those of the Adam Project must devour the flesh of an Angel. In doing so they acquire instantaneously all the powers of the second, making them God-like.
It is first mentioned by Adam Arclight that his goal was to be the next "The Second Christ" by bonding with one of the two first Angels that arrived on earth. The one who chose to hibernate deep underground to recovers its powers. Arclight revealed that one of the reason that Simeon Company chose to build its building at the very epicenter of the black spot is to excavate that very angel.
This god like ability is directly connected to a Dimensional Gate/Rift. The supply of Dark Matter allows the user to maintain their god-like abilities. Closure of the dimensional gate would only allow a brief period of reality warping, but would still maintain the previously rewritten reality. The fragment Shield of Aegis can be considered its Anti-Thesis. The very nature of the Shield of Aegis negating Dark Matter energy sequentially closes the dimensional gate but also depletes the additional dark matter energy maintaining the god-like abilities.