This is the magic system I've derived from the old European understanding of elements (often referred to as alchemy) as well as the Five Elements or Wu Xing that has origins in China (waaaay before Christ died for our sins n' all). And yes, Avatar and Naruto had their part to play—I even hear I may of unintentionally taken concepts from Dungeons and Dragons and Warcraft 😼
The four first-order (fundamental) elements are Air, Water, Earth and Fire, and these can form hybrids or terrastrial second-order elements: Freeze, Wood, Spark, Magma, Dust and Steam.
We also have third-order celestial elements, which dictate higher-level mechanisms of the universe: Spirit, Body, Light and Dark.
The fourth-order element (i.e. accumulation of all fundamental elements) has been omitted from this chart, but is usually referred to as Origin. It can't quite be comprehended, but it is thought to be the missing link for the secret to human life—as suggested by the "mortal bridge" (see below).
All elements hold a transcendental state, which is futher description to what the element is responsible for in the universe. Dust, for example, relates to "falling", causing the gravity for humans on Earth to the formation of stars.
The projection axis and entropy axis can be used to approximate an elements properties. The fundamental elements form the basis of the chart's orientation, i.e. Air (void) and Earth (material) is a spectrum of things materialising (projection), and Water (calm) and Fire (excite) is a spectrum of things moving (entropy).
Light and Dark are the only elements to which the P-E axises do not apply, although their position above and below fire-water respectively comes from an untested notion of their unbounded entropic value. They are, if crudely, understood by mortals, and so can be manipulated at will if a Magi masters the respective fundamental elements.
The mortal bridge is the collection of elements which collate the existence of beings that can observe the universe, like us. Commonly referred to as the Genesis of Life. It consists of Spirit-Spark-Steam-Origin-Dust-Wood-Body, which are the elements that occupy the top-left to bottom-right diagonal on the chart. Spirit and Body exist in strict conjunction with the mortal bridge, only have theoritical purposes so far in the known literature of elementary study. With a seemingly unsurmountable effort of manifesting the key Origin element too, no one has managed to master nature itself—no one we know of, at least.