Imperium is the metaphysical arcane power available to every living creature, as described in the Second Law of Magic. Some species or individuals are more easily able to tap into this resource, while others require a Focus. Each individual has a limited internal reservoir of Imperium, which they spend according to the strength and quantity of their spells cast. Once an individual's Imperium is depleted they must replenish it, either through rest and meditation or by other means.
Origin & Source
All living beings possess natural processes to convert nutrients into the fuels needed by the body for survival. Imperium is created in the same way, internal to the individual rather than from an external source. All living creatures metabolize their own Imperium, unknowingly tapping into the magical fields present across Fillimet to complete the process. Naturally Unattuned creatures and individuals will produce only a small amount of Imperium, while those Naturally Attuned will produce a larger reservoir. This natural resovoir can be expanded through regular practice or exercises. Once the reservoir is full the body will cease Imperium production unless some of the stored Imperium is used. Due to the energy required to manufacture Imperium most creatures including all sapient species are more efficient at manufacturing Imperium while sleeping. Some meditations are also able to tap into this process and stimulate the individual's metabolism to manufacture additional Imperium. Certain nutrients can also be ingested to restore Imperium reservoirs. The safest methods involve a delay between ingestion and production, such as the ingestion of arbitrium which can be metabolized directly into Imperium when needed. Others such as tea from the Imperial Night Rose provide Imperium directly to the bloodstream, with potentially devastating consequences. If a creature is starved for sustenance their internal processes prioritize the production of physical energy first and only then will they use any leftover resources to manufacture Imperium. For this reason a severely malnourished individual will require not only nourishment and physical healing but eventually regrounding to realign them with the magical fields and allow them to produce Imperium once again. This ungrounding from the fields is not life threatening but does feel emotionally uncomfortable for the sufferer, due to their disconnect from the familiar but subconscious energy of the fields. It is important to note that Transitory Ungrounding is not to be mistaken for Unattunable Disorder, which is a permanent disconnect from the magical fields. Magic has no direct impact on an individual suffering from UD, while Transitory Ungrounding can only be treated through magical means.
History & Usage
Most individuals use Imperium on a daily basis, some without even realizing. The Naturally Attuned can tap into their Imperium with minimal efforts while the Naturally Unattuned require some form of sentimental Focus to do so. In each case small spells become a natural and subconscious part of the day whether it's to nudge an object on a high shelf a little bit closer or improve focus on a distant object to see it a little bit better. Those trained in the use of magic are able to use the magic on a more conscious level, and cast more powerful or focused spells as a result.
The use of Imperium is not without risks. Creatures change with regular exposure to magic, dependent upon the nature of that magic. Some of these changes are quite harmless or even welcomed, such as the colorful Portal Marks from extensive exposure to Interdimensional Magic. Others are dangerous, such as the devastation of Calamity. Exposure to raw, concentrated Imperium is also quite harmful for most creatures. An individual can safely store enough Imperium to fill their personal reservoir, as the body has adapted to safely mitigate its effects. Direct exposure to a more concentrated dosage, or even a higher volume of Imperium, can cause physical scars or burns as well as permanent mental effects in the form of Hallucinatory Imperium Oversaturation.