The Apostles
At the beginning, there were only 6 apostles that were the concept of the very things themselves, holding immense Monster Power, so much, that they are not able to stay in the material world that we know of and live. They were:
1st, The Authority, twin of the:
2nd, The Power.
3rd, The Body, twin of The:
4th, The Memory.
And the 5th, The Time, twin of The:
6th, The Aether.
The Authority represents the Will of God. An absolute ruler. The Power Stands as the very forces in the Universe, including the natural ones, such as Thunder, fire, plasma, etc. The Body is basically the Life itself, the Genesis, and the one that created Organic Matter, the very life. His twin, The Memory, is the one that holds the Consciousness of these living beings. She is the Adaptation, The Dreams and The Basis of a complex thinking being. The Time is, well, The Time itself. Think of it as a game; the things of the Universe just rendered and played because of him. His twin, The Aether, is the Place of the Game. He is the Space and the vacuum. He created and is the Universe Size himself.
Then, for some unknown reason, these sixth base apostles decided to create another 6, forming the first Twin Apostles and the Second one.
These are the others:
7th, The Darkness, with their twin, The:
8th, The Light.
9th, The Truth, with their twin alongside, The:
10th, The Fantasy.
Then, there is...
11th, The Destruction, with his twin, the:
12th, The Creation.
The 7th not only encases shadows and the absence of light; it is the Profane. The one that most doesn't relate with God itself. Then, their twin, The Light, is the very opposite. They are the Bless of God. The one that shows everything and the Good.
Then, there is the 9th, The Truth. While they supposedly are the creator of the Laws of the Universe and Gravity, Everything that they say or think comes to be true. While their difference with the 1st is Not so large, they are a substantially important Apostle with their twin, the...
10th, The Fantasy. It is the Concept of Lie, the one that possibilite surpass the Laws of the 9th briefly and do changes that remain for ever in the Universe. Some Examples are Rituals and Magic, though it sounds a bit silly, they truly exist and are in the 10th Dominion.
The 11th, The Destruction, is the Very Entropy Themselves. The Concept of deleting another one, but their descendants only have enough power to delete or obliterate literal mass or matter, though not reaching it's maximum potential. And, then, there's finally the 12th, The Creation. The ability to form things quickly, complex objects to pure mass. With Infinite Monster Power as any other Apostle, it could supposedly Create an Infinite Range of other Universes and worlds, from the Plain Ground to the Complex Life.
How do Apostles interact with the Material Universe? Well, though it all has come from them, They can't interact with it as they please due to their unsurmountable amount of Monster Power. So, to do that, is required a fine and huge amount of prepare from their Chosens, which are able to communicate with their Apostles and do their chores and obligations of the Material World. Given that and a huge stress and preparation from their Chosen's part, finally, they can go to the Material World through Avatars. Avatars are their Flesh side, containing a decent Amount of their Power, enough to be for sure Invincible to any other being that's not another Apostle. But, of course, how do they are all still locked in the higher planes? Well, when they take their new Vessel, their power are still so surprisingly strong that, in weeks, it grow close to what their trueselves of the higher plane are and they are forced to return to the Higher Plane.