Magic

Fundamentaly there are four sources at work, in order of magnitude these are; Primal, Divine, Arcane, and Psionic.
Primal power was at work in the creation of the multiverse. The Elemental Chaos is raw Primal power, this is the source at work at the most fundamental level, holding our universe together in it's parallel with the rest of creation, while simultaeously pulling it apart at the edges. Nature is itself, owed to the Primal, and it's spirits soar along ley lines of primal power.
Primal power is unrestricted in form at it's core Primal power is morphic, unpredictable, and terrible in it's destructive capacity. However, it must be emphasized that primal power is also the source of creation, thus life-giving.
Divine Power is derived from the Gods it was constructed along a great lattice, and with a wisdom that accounts for it's omnipressence which rivals the Primal. As the deities sought to protect the creation whilst the primordials sought to destroy it and start again, the Gods' power was necessarily versatile and capable of ruling the entirity of creation. As such Divine power is able to rend and restore life, raise the dead, either through restoration or necromancy (a magic shared by the arcane). Divinity's form is largely contingent upon the specific deity from whom it eminates. Thus, Bane's power is often manifest in how wars are won and rule maintained, as those are subjects of that god's portfollio.
The Arcane is a much newer power source, in terms of the fundamental forces at work in the multiverse. The Arcane is also more difficult to access, requiring complex gestures, components, and rituals to effect even the simplest manipulations. However, reliable laws known as the Corpus Arcanum detail how certain energies will react in given circumstances, and it is largely free of entities controling it's fundamental precepts. The Arcane is the most potent means by which the mortals can manipulate their environs. Being a Power source of incredible power, the Arcane is capable of a great many effects. These having been divided into Schools by the foremost scholars and arcanists of the mortal worlds, are limited only by imagination and relative intelligence. Though for some reason as yet undiscovered, the restoration of living things is restricted from arcanists being the perview of other sources. Arcana is woven rather than built, many have described it's manipulation as being akin to drawing upon particular threads and "weaving" spells together. The schools of magic are; Transmutation, Illusion, Nethermancy, Necromancy, Enchantment, Evocation, Conjuration.
The Psionic is a force derivitve from the mind. There is much evidence to suggest that it has a great deal more significance in the dimension known as the Far Realm. Essentially, the Psionic is the manipulation of the external world through the manifestation of focused mental energy. The practitioner of psionics is known interchangeably as psionicist and psion. The effect of psionic power has been seen in numerous ways, telepathic, psychoportative, transformative, telekinetic, precognitive, and projective. Telepathic psionics have to do with one mind accessing another in some way. From the simplest reading of surface thoughts to the devistating mind blast.
Psychoportative psionics have to do with the transportation of the psionicist from one place to another. Transformative psionics concern thselves with the changing of the material, largely this branch of psioncs is unexplored as it is quite deadly. Telekinetic psionics allow the psionicist to manipulate their environment through a mental force. With telekinesis a psion is able to lift objects into the air, hurl them at enemies, and even fly with intense effort. Precognitive ability allows the psion to gain sight across time. A precog can see visions of the future. Sometimes this power manifests itself in the ability to "read" objects; gaining vision of the object's past. Precognition also allows for clairvoyance, clairaudiance.
Finally projective psionics involve the extension of the psion's senses into other planes of existence. This also applies for the extension of other psionic beings into our plane of existence, as the entities from the far realm have done, as have demons and devils. Projective psionics are most often used to allow the psion to sense things via the astral plane. Astral projection is a difficult and powerful task for a psionicist, however, once mastered can allow such a practitioner access to a vast array of power and information.
Though the term "magic" isn't exactly applicable to all these functions, it suffices for the current understanding of our multiverse. It is difficult to understate the significance of these forces in our universe, and those as yet undiscovered other universes. Magic simultaneously holds our worlds together and pulls them apart, and our understanding of its intricacies are woefully insignificant when compared to its unknown awesomeness.