Technomancy

The Celestials, after using more primitive 25th century technology to drill into other dimensions, eventually found some planes (such as Limbo, the Astral Sea, and later the Far Realm itself) where physics behaved utterly differently from that in our universe, and that the behavior of matter, space, and time itself were in those places linked to the very minds of the inhabitants of those realms. Quick to adopt this technology for themselves, the Celestials were the first to practice technomancy, what the inhabitants of Yorth would later refer to simply as magic. With technomancy, individuals could manipulate the world around them using only their own minds. Eventually the Celestials created the Weave, a flow of technomantical energy entangled forever with the Cosmic Microwave Background radiation of our universe, so that individuals anywhere might draw on it and use technomancy themselves. This would forever change the trajectory of the universe, as civilizations across space suddenly had access to power they had never even conceived of on their own. Some call it the greatest achievement of the Celestials, others their greatest mistake.   How technomancy functions is an elegant intertwining of brain chemistry and matter and space-time through the medium of quantum entanglement. After the creation of the Weave, access to technomancical effects can occur anywhere in the multiverse, except where precautions against such things have been built. Spellcasters may access technomancy in any number of ways: scholarly study of it and the means to access it (i.e. wizardry), have access granted by a being with a more intimate knowledge of the Weave and how to use it to manipulate reality (i.e. cleric and warlock patrons), sheer force of will forcing interactions between the brain and the Weave (paladin oaths, the performative technomancy tapped into by bards), an inherent biological ability to access the Weave (sorcerer bloodlines), or through a somewhat "accidental" connection to the Weave as it flows through all of reality by means of a more spiritual connection to the natural world (the shamanistic technomancy of druids and rangers, or the meditative practices of monks).   The Weave permeates all of reality in Anuwai, and so after its creation, the multiverse changed in ways which, to the layman, could only be described as magical. Instant communication across vast distances, interplanar travel, teleportation, the ability to affect the minds and bodies of the self and others, the conjuration or destruction of matter and energy seemingly from nowhere and more all became possible with the creation of the Weave. Naturally, this resulted in a technomancical arms race across the multiverse, and after many devastating wars were fought costing untold lives and resulting in the destruction of entire civilizations, worlds, and even whole star systems, in a great many cases limitations on the power of technomancical effects were put in place, and restrictions to Weave access were enforced in a great many cultures.