Chrono is the name given to the essence and origin of all magical effects throughout the Ealdremen system. It is used as a source of energy for both living creatures and technological marvels, and it occurs naturally in every known part of the solar system.
When used, Chrono becomes temporarily inert and unusable for anything else; this phenomenon is known as "burn" colloquially due to being viewed as similar to burning through kindling and a fire going out for lack of fuel. However, unlike the proverbial firewood in this example, Chrono does naturally replenish over time. In living organisms, it tends to replenish itself over the span of several days with enough rest, but severe usage of a living organism's Chrono can result in injury or death. Chrono can also be drawn directly from the environment or harvested for later use, but doing so safely requires precise measurement tools to ensure that the area is able to replenish itself later.
Typically Chrono is invisible to the naked eye, but in dense enough concentrations, it becomes visible as a translucent colored aura. Most often, these auras are short-lived bursts from the activation of something utilizing Chrono, such as a spell or a powerful machine relying on magic as a source of energy. Afterwards, the Chrono becomes inert and remains in the environment until it reaches a natural equilibrium with other unused sources of Chrono and becomes usable again. This process' duration depends on the strength of the effect and amount of Chrono used; weaker effects such as from an individual's spell tend to reach equilibrium within ten days, but longer-term or stronger uses of the environment's Chrono can take years to restore.
It is possible for Chrono to become so tangible in the environment that it remains visible long after the "completion" of the magical effect. The most common source is an excess of Chrono such that the inert Chrono from a spell or machine cannot reach equilibrium and pollutes the immediate surroundings, which cascades into adjacent areas if not contained. These Chrono-contaminated areas can be lethal to living creatures and cause malfunctions in inanimate machines or warp objects. As such, despite the potency and availability of Chrono as a source of energy, it has not displaced more "mundane" and "limited" forms of energy entirely, and machines that utilize Chrono tend to only do so sparingly, relying on Chrono strictly for uses that other forms of energy can't replicate.
Origins of magic
Modern understanding of Chrono and its applications categorizes the usage of magic, whether by technology or individual, into four distinct sources: Learned, derived, bestowed, and gathered. A given user of Chrono can conceivably draw from multiple sources to varying degrees, but it is more common for there to be a single source or at least a primary one.
Learned magic
Learned magic structures casting and artifice into discrete spells with codified effects, methods, and parameters for use. Such magic is often taught in institutions of learning dedicated to the craft, and practitioners of this form of magic tend to see the usage of Chrono as a science with rules analogous to chemistry — while one can deviate from established practices, doing so is dangerous, and it is better to always follow preset guidelines outside of controlled environments meant for safe experimentation.
The guiding principles behind learned magic are rooted in scientific theory in getting reliably the same outputs with the same inputs and modifying those inputs until a perfectly replicable spell is established. Innovation is something to be done in research and theories, only brought out into the field for "testing" once rigorous trials have been passed in controlled environments. Numerous organizations exist throughout Ealdremen dedicated to dictating proper practices for magic and detailing repositories of established spells.
Some institutions focusing on learned magic consider the learning and documentation of all forms of magic — not only just learned magic, but also derived, bestowed, and gathered magic — to be part of their purview. This empiricist perspective of magic has also resulted in views that all magic can inherently be categorized and "ordered," and it is from learned magic theorists that magic can even be categorized into distinct categories such as learned magic. As such, learned magic often forms the basis of many individuals' education in magic and the casting of spells, and widespread enough theories and practices can be seen in all forms of magic, not just individuals who associate with learned magic in particular.
Under the living Ealdremen theory which posits that magic exists because the universe itself is a living organism, learned magic is referred to as Ealdremen's brain.
Derived magic
Derived magic is also known as innate or bloodline magic, though the latter term has fallen into disuse with the advancement of implants and augmentations that can bolster an individual's innate Chrono to the point of being able to cast spells. While those with strong ties to Chrono can learn how to control this ability through a variety of sources, including institutions or individuals more commonly associated with other forms of magic, the most common practice is for such individuals to have a personal tutor much as one might serve as an apprentice to learn a skill. These tutors tend to have multiple students which then practice together in structured environments on a regular basis.
Although derived magic is broadly understood to be genetic in nature, it is the most complicated question for biologists to answer. Intuitively, someone related to individuals with strong ties to derived magic is likely (though not guaranteed) to have similar ties themselves. However, it has also been documented that individuals related to practitioners of other types of magic can display derived magic, with some studies even suggesting that this can occur even if an individual's relatives begin to practice magic after they were already born and presumably would already have a genetic tendency towards or away from Chrono. It is unknown if this is cultural or sociological, if it simply indicates a correlation between particular genetic strains and eventually developing an interest in magic, or if this phenomenon is documenting a warping power of Chrono.
There are some arguments about derived magic not being a true source of magic unto itself and simply being an inclination towards magic, just as an individual might be naturally inclined towards the arts, athletics, or any number of things; the existence of people who are drawn to these subjects does not mean the subjects originate from the people.
Under the living Ealdremen Theory, derived magic is called Ealdremen's genes.
Bestowed magic
Bestowed magic is granted from another power, such as a pact with a creature from the Ravel, the binding of numina, or the worship of at least one god. It is distinct from apprenticeships in that a tutor of mentor does not grant magic to their students; these students have innate potential or preexisting abilities in using Chrono as it is and are being instructed by a tutor for safe practice of their developing skills.
Some theorists believe that bestowed magic is a subset of derived magic, instead obtained through willpower and faith manipulating an individual's innate reserve of Chrono. Under this idea, "bestowed" magic is merely derived magic molded by faith that the magic originated from a higher power of some sort. Such theories are especially common in cultures with strong mixes of spirituality and scientific advancement where the latter attempts to explain the former through its own lens.
Of the forms of magic, when used by individual people and not by inanimate objects, bestowed magic tends to overlap with gathered magic, which is using Chrono from the surrounding environment. This is due to the frequency of animist beliefs and the worship of nature or the world itself as a god throughout a myriad of cultures. As a result, it's often unclear if these forces are undocumented but possibly verifiable phenomena capable of granting magic to an individual, or if an individual is simply drawing upon environmental Chrono with the perspective that the environment (or something within it) is granting this power.
Under the living Ealdremen theory, bestowed magic is called Ealdremen's consciousness.
Gathered magic
Gathered magic utilizes Chrono from the environment to empower magical effects. It is sometimes called artifice magic due to the frequency in which it is used for powering inanimate objects. Comparatively, it is rarer for an individual person to strictly or even mostly rely on gathered magic and not have their connection to their surrounding environment be regarded as faith-based in nature and consequently a form of bestowed magic rather than gathered. However, there have been documented cases of individuals being placed in environments solely with inert Chrono and being unable to cast spells while those deriving magic from other sources are able to cast in the same environment, indicating that it is possible for individuals to be unable to utilize their own innate sources of Chrono and to solely rely on the environment.
Although gathered magic is often associated with the worship of nature, especially "untamed wilds" such as expansive untouched forests, the depths of oceans, or inhospitable desert climes, it has been found to occur in "unnatural" environments as well, including aboard space stations or in cities, where individuals using gathered magic may run the risk of depriving important infrastructure of power if they cast too powerful or too frequent spells.
It has been theorized that the cancchia species, uniquely inert to Chrono and unable to utilize magic in any form, may be able to use gathered magic as a replacement for their bodies lacking in any Chrono if a device were created to "mediate" the cancchia's body and their surrounding Chrono.
Under the Living Ealdremen theory, gathered magic is called Ealdremen's body.