Deep Magic

The Deep Waters are an arcane source of elemental power that seems to defy the laws of Cosmic Energy by allowing for the bypass of the “gates” normally needed to establish cosmic connection and cast magic. Instead, by becoming imbued with the Deep Waters, an individual is able to become their own mana source, casting spells independent of the surrounding circumstances.
On the surface, this looks like a divine blessing, not unlike what is used by agents of the church when they become able to use holy magic, but that's simply not the case. In those instances, the deity simply opens the gate for the mortal, allowing them to use the power of Celestia without having to learn to open it themselves. The same is true for Demon magic, as it uses the dark energy that is the Demon and its link to Pandemonium to fuel the spells. The Deep Waters do not draw from the cosmos, they are sources unto themselves. According to teachings on The Deep, this is because the Waters are the cosmos, but further research is needed before that will be made more than religious belief.
As a result, no one can be certain where or even really what the Deep Waters are. Those that experience them say that they are transported outside of themselves to a body of water. What this looks like is dependent on the specific Water that is being dealt with, but there is a trial that must be completed in order to obtain the right to drink. These trials are created by the Deep Ones, apparent vessels of the Deep Water, that are able to shape certain aspect of these pocket domains. Once they drink, they are back to the mortal world, now with the power of the Waters within.
The prevailing theory among Arcanologists is that the soul - something made of Cosmic energy - is replaced with the raw "stuff" of another realm. Be that pure lightning, psychic, fire, etc., thus supplanting the caster's Soul. This has the after-effect locking off all other options for elemental spellcasting.

Type

Metaphysical, Arcane