Estus

Estus is essential to the most basic magical technique. Through various methods, it can be controlled and manipulated to create magical affects that would not be possible naturally. Ordinarily, estus isn’t visible, but when highly concentrated and manifested in large amounts, it has an orange flow. Aside from it being a fuel for magic, it’s also a fuel for life as it's required and possessed by all living beings, and possessed to some degree.

Origin
Originally, estus was a life force only possessed by Malchor, the god of creation. Before his reign, the realm of Idris was a massive planetary rock, a barren wasteland without life. Using estus, Malchor created the first plants and animals as well as shaped the land and created the oceans from his own blood. When he desired a companion, he split his estus in two and used one part to create a new being: Rheda. When they fought in the end of the Lost Age, the estus which remained in their deceased bodies manifested into the Children of A New and they used it to create the various downworlder races in the realm of Idris. Okysus was also born with Estus, though as a naturally created being, he did not have his father's nor his mother's but his own.

Overview
Estus has become a form of life energy that all living beings possess and produce to some degree, therefore it goes without saying that if one were to run out of estus, they would die. Those who wish to use magic must first learn how to generate estus from their reserves and how to manipulate it when called. With practice, one can learn how to easily generate their estus, to the point to where they could even generate all their estus, however there is a limit. Every being is limited to their maximum amount of estus that is gifted to them by their genetics. While generating more estus from their reserves can be taught, increasing how much estus one possesses in their reserves cannot, limiting the magic of individuals. Similar to DNA, everyone's estus has its own unique signature.