Divine Magic: Arcanism

There currently exists one discipline of Divine magic; Arcanism.
By focusing on the soul, it is possible to separate it from the body in a process called 'Astral Projection'. In this state the soul is able to press through the barrier to Altera. Given the nature of Altera, its not possible for our minds to fully comprehend or even fully perceive the plane of Altera. We are, however, able to interact with the spirits that reside in Altera. Spirits often do not have a personality, they exist as impulses of the domain they represent. As spirits gain in power and age, they refine themselves, becoming more defined and, eventually, evolve into a lesser god of their domain, gaining sentience, a distinguished personality and become what is called an Arcanum (Arcana is the plural of Arcanum).

Arcana are able to be conversed with, and have the closest spiritual makeup to humanoid souls than any other being we are aware of. This similarity of spiritual make up allows a practitioner of Arcanism to bind the Arcanum to their own soul.
Binding an Arcanum is an agreement between Arcanist and the Arcanum, some Arcana will talk to the Arcanist, some will wish to fight to test the Arcanist mettle, while others may seek a battle of wits, or even a show of affection. Each Arcanum is unique and while it does seem there is some correlation between an Arcanum and their domains they represent, its not always the case, and may not be a good representation of who the Arcanum may be as an individual.

Bringing the Arcanum through to Subcaelum is called the act of Summoning. In order to summon, the Arcanist focus their will on the connection to the Arcanum they wish to summon, and weakens the barrier to Altera, this is done by focusing their Will, using an incantation to verbally reinforce their mind and Will. Once the barrier is weaker, the Arcanist attunes their own soul to the domain of the Arcanum, acting as an anchor point in Subcaelum for the Arcanum to resonate with, which allows the Arcanum to step through the weakened barrier and into this side of the barrier from Altera. The spiritual attunement will resonate between the Arcanist and the Arcanum, a link between the two providing power based on the domain, this will bolster the Arcanists power and provide magical domain boons to them, this phenomenon is called Merging and is a natural side effect of Summoning an Arcanum.

As Arcana are from Altera, they are constantly pulled back to Altera. Maintaining a summon, or a merged state, requires a constant state of focus, given this, its impossible to maintain a merged state forever. Once the Arcanists soul no longer resonates with the a domain of the Arcanum, the merged state will end and the Arcanum will return to Altera. This is called Dismissal.
There are two methods of Dismissal; Graceful and Charged.
Graceful dismissals is where the merged state ends without strain or focus being put on the connection between the Arcanist and Arcanum. This can be done by the Arcanist simply releasing the spiritual resonance, an abrupt spiritual interruption through any means, or the loss of consciousness of the Arcanist. The main reason for Graceful dismissals is that the connection or spiritual resonance has been ended without flare or effort.

Charged dismissals on the other hand are deliberate and is a somewhat violent method of dismissal. Rather than releasing the connection, the Arcanist and Arcanum put a great deal of power into their connection, strengthening it as powerful as they can, before immediately releasing their spiritual attunement. This abrupt ending with great power being stored in the connection acts like a loaded spring immediately snapping, launching a great deal of power to the Arcanum. In the instant before going back to Altera, their power immediately bursts outwards into Subcaelum. This is a powerful and dangerous method of dismissal, and while the Arcanum and Arcanist are usually not at risk during a charged dismissal, the same cannot be said for those in the immediate vicinity. Use with caution.

Summary of Summoning:

1. Focus will on the barrier to Altera, chanting an incantation.
2. Resonate the casters soul with a domain of the Arcanum
3. The Arcanum steps over the boundary into Subcaelum, merging with the Arcanist