Aer

General

Aer is the lifeblood of all that exists. Everything in existence is made of Aer, and Aer itself is made out of eveything. From each drop of water in a river to every single ants in a nest, even time, hope or love, everything physical or intangible, every object and every concept is made of Aer. Invisible, volatile and unstable, Aer is as much a substance as it is a liquid or a force. It's what holds Aedrelon together and binds it to reality. As such, if something would become devoid of Aer, it would simply cease to exist and disappear.
While it can't be seen, Aer can still be felt, and the density of Aer in any given environment has many consequences on said environement. For example, a place where high Aer is particularly dense would be lush, filled with life and many species of animals and plants, or even host plenty of anomalies. Indeed, as the heart of all that is, Aer can spontaneously birth anything into being. On the contrary, places with a low density of Aer will be harder to live in and often look barren.

Art & Artists

Some beings are able to Burn the Aer that composes them in order to alter the world around them and accomplish miracles. This practice is called Art and its practitioners Artists. The powers of Art are, like those of Aer itself, virtualy limitless and are only bound to the Artist's own Aer and limits. Indeed, all things that exist are made out of a unique "color" of Aer that burns in ever so slightly different ways. This color, as well as the shape, intensity and warmth of the resulting fire, is the Arcane Signature of that one being, and dictates what kind of miracle an Artist is able to perform : namely the Movement they are able to use. Movements are the five basic Arts from which all others are derived. One may never learn another Movement than the one dictated by their Arcane Signature.
No catalyst is required to practice Art. Only the Artist's will and skills are put to the test. Even though some prefer to use precious wands or staves, old dusty grimoires or strange words in forgotten tongues to channel their Aer and bring forth miracles, these tools have no real effect other than help the Artist focus. The practice of Art is also one of the only moments where Aer can be seen. As the Artist burns their own Aer, it manifests as little flames, sparks and puffs of smoke and ash on the Artist's body.
The only condition for a being to be able to practice Art is to be born with a Flame. The Flame is almost like an ethereal "organ" that allows one to burn their Aer. All Da'Kaers are born with a Flame, as well as some rare species of animals and plants. However, it is important to note that the practice of Art is not without its risks. Indeed, as it requires burning one's own Aer, it is crucial to be mindful of one's limitations : if all the Aer that makes a being is consumed, that being disappears entirely. The Aer contained in most being replenishes as they stay in contact with the one around them.
Aside from a select few exceptionnal beings, no one really knows all of this. For almost all the inhabitants of Aedrelon, Aer and Art are nothing more than strange esoteric forces that they have to live with. Some dedicate their entire lives to its study in the hope of uncovering its many mysteries, but each discovery only seems to create new questions.

Arcanas & Paths

Aside from the five basic Movements, Art also exists in the form of Arcanas and Paths. They are forms derived from the five Movements that can be learned and mastered, with enough training, by any being able to practice Art. While a basic mastery of the associated Movements can ease the learning process, it is not needed to develop a proficiency in any given Arcana or Path.
Almost an infinity of Arcanas exist throughout Aedrelon, but only a few are widespread enough to be recognized and studied as their own disciplines. Some are shared by entire cultures or communities while others are limited to very exclusive groups of people, or even to completely unique beings at times. The volatility of Aer makes it so that compiling a full cohesive compendium of all its abnormalities and all the forms of Art derived from them practically impossible.
As opposed to the empirically discovered Arcanas, born from the whims of Aer, Paths are forms of Art entirely constructed by a group of individuals. They are built on the idea that communities and rules can shape the people bound to them. Thus, when one decides to bind themselves to the rules of a Path, they gain the powers developped by that community. These powers are largely held by beliefs : they exist and manifest thanks to the common acceptance of their reality. So, if the community that built it were to disappear, the powers created by this community would disappear with it. Likewise, one a follower of a Path were to leave the community or break the rules of the Path, their power would also disappear.  

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