Magic is different depending on where one is, and the world in which they reside. There is a universal magic that applies everywhere, its rules immutable and far stronger than any magic from which it descends.

Universal Magic

All magic requires power, energy. Something cannot arise from nothing.
Knowing the name of something gives power over it.
All souls contain an essential vitality, energy, which can be used in the absence of any other power to fuel spells.
The transference of vitality from one thing to another requires, in at least some part, sacrifice on the part of the transferer.

A form of magic that operates entirely under the principles of universal magic is true names. Indeed, unlike all other forms of magic, the invocation of true names is just the practical application of the four rules.

Souls

The essential vitality that lives on even after death. Souls are what empower magic, the difference between a cantrip and a true spell being to what degree it uses the power of a soul. A magical act that would use less than the full breadth of a soul to cast is considered a cantrip; these actions can be performed essentially infinitely, without draining a soul of all its vitality. A spell, by contrast, will consume all the vitality of one or more souls in attempting to cast it.

When someone is alive or their soul is otherwise inhabiting a living body, their vitality will always restore to their capacity over the course of a full night's sleep. In the event that they are unable to enjoy a full night's sleep, their magic will not restore whatsoever. A character who is either projecting their soul outside of their body, or otherwise not inhabiting a living body, must find alternative means of restoring their soul

Transference

Anyone, no matter their proficiency with magic, if they have a soul they may choose to grant power to another. This power cannot be granted easily, however. For a consensual transference of power, it must be in the form of a sacrifice. These sacrifices can be as subtle as acts of worship, they need not necessarily be grand displays of power.

There is also, of course, transferences of power that are not consensual. This is often in the form of cannibalism. Eating another person requires no special magic, no technique, no practice. If someone is eating the body of another, then each morsel will imbue the cannibal with the essential power of one soul. If the cannibal eats the heart of their victim, then they have by this same token eaten their victim's soul.

Capacity

The capacity of one's soul is measured in souls. Because some souls are inherently more powerful than others. The worth of a single soul, for the purpose of magic, is thus:

A fireball, roughly 3x3x3 meters.
Lifting and moving something weighing up to 100kg for one minute.
Shoving something up to 200kg back up to five meters.
Conjuring up to 1kg of material in any shape or configuration that the caster can imagine.

The only way to raise one's capacity for power is by the consumption of other souls. For characters, this is reflected by a trait on their profile if they have consumed more than one soul. When someone's soul is consumed, the whole of their power goes into them. Meaning, if that character had two souls worth of power, the person who ate them now has three souls worth of power.

If a character eats something that is in excess of ten times the amount of power they possessed previously, that character becomes irradiated with magic, as the power is more than they are ready to sustain.

Some characters, or entities, have altered their own souls to be able to consume the souls of others in ways other than blunt cannibalism.

Final Death

When a character has had all the power of their soul consumed, when they are too weak to take power from others, they are essentially dead. Their souls may still be conjured, but they retain no memories past the point where they died, and they cannot take meaningful actions beyond what they are imbued with the power to do. The moment they are no longer being sustained by the power of something else, they are dead again and retain nothing of the time they were conjured.

Antimagic

The known means of directly counteracting magic.

Invocation

This is not quite the same as antimagic, though. If one learns its true name, they have power over it; that power may then be used to deflect, or it could even unravel the entire system of magic altogether. If one knows the true name of a source of magic, then they will be able to control the source of magic itself. That could mean simply canceling out spells they don't like, but could very well unravel the system of magic altogether.

Soulless

Characters with the soulless trait cannot use magic, unless the magic relies on a source other than their own soul to conjure or direct the energies involved.

Countering

The more common form of antimagic is countering one spell with its inverse. Life cancels out death; fire cancels out water; and so on. The only caveat is that the spells must be of equal power, and actually come into contact with one another. A clever mage can bypass a counterspell by just maneuvering around it, while a powerful mage could simply overpower it.

Attunement

There are two forms of attunement: domain attunement, and spell attunement.

Domain Attunement

To be able to cast spells of a particular domain, a character's soul must in some way embody that domain. This gives them access to minor magical abilities of that domain, and it may have other tangential effects as well. There are several ways to attune someone to a particular domain: possession, imbument, bartering, and so on.

Spell Attunement

The amount of spells a practitioner can be attuned to is affected directly by their Erudition and traits. This is different than the amount of spells they have the technical knowledge of how to cast. Changing what spells a character has attuned requires one hour of uninterrupted meditation per spells being changed as they align their soul to channel different magical powers.

A character cannot attune to a spell they don't know. If it has been a long time since they have attempted to attune to a spell and they haven't a grimoire handy, a DM may choose to complicate the attunement process in some manner.

Grimoires

A grimoire is not strictly necessary to cast spells. However, even the most minute change in how a spell is cast can result in an extremely different outcome. A grimoire, simply a repository of instructions on how to cast any given spell the caster is attuning themselves to, is necessary to avoid mistakes.

If a character is attempting to cast a spell they have attuned without a grimoire, at the moment of casting they must roll a d100.

1-10. The spell is forgotten. The spell results in a disastrous outcome for the caster, as determined by a DM or mutual agreement between everyone involved.
11-39. The spell is forgotten. The spells unambiguously fails, and resulting in a bad outcome for the caster, as determined by the DM or mutual agreement.
40-60. The spell is forgotten. The caster decides the outcome, within reason. If casting this without a DM present, just treat the spell as a success and its intended effect happens.
61-100. The spells works as intended.

Ayarian Magic

The kinds of magic on the world of Ayaria are mainly descended from the Hours, or if not the Hours directly, then from Ayaria herself. Without Ayaria, there would be no magic on that world and it would be impossible for the Hours to have changed it so dramatically. It is said that when Ayarian magic was made, each of the Hours learned each of the twelve parts of her true name and then together infused her essence into the world and created the magic systems they would use.

The laws of Ayarian magic:

The part is equivalent to the whole. One is able to target Ayarian spells with only part of their target's true name. One is able to cast a spell on a fragment of a thing, and be able to manipulate the whole thing; or, target the whole of a thing and the same spell still affect the fragments.
Bridges go both ways. When a connection is formed between two things, both sides are able to interact through this connection regardless of the intent of the one who bridged the connection.

Empyrean Magic

All throughout the history of the Empyrean Empire, they had a complicated relationship with magic. Early on, attempts to destroy all records of magic were partially successful. After the War of the Theologians, part of the compromise that emerged from that resulted in the rise of universities that specialized in one or more given kinds of magic, and it became broadly accepted across the empire even if mages remained somewhat rare.

After the Fall, attempts to preserve the magic were made. These attempts largely failed, as vast troves of knowledge have not only been lost, but outright destroyed. The machinations of elves and Valleymen, among other more esoteric forces, sought to prevent the rise of man again. So they sought out any and all persons who knew of, or in some cases were even capable of magic.

What little knowledge survived the next several centuries did so in absolute secrecy. Empyrean mages were known generally as wizards or magi, but more often referred to by their specific school. At their height, they were a major political force in the empire, so more is known about their influence on politics than about their magics.

The Five Schools

While there are many lesser schools of magic that the Empyreans sometimes explored, quickly the field of magic became dominated by the five largest schools. These made up both a large political block, but also dominated the scholarship of the time. At least in the field of magic.

Each college of each school has its own associated domain. The domain is embodied by a deity, one whose true name was captured by the Empyreans. History tells us that the name would then granted to a slave, who would twist the god in a way not unlike the twisting of the original Ayaria into making a boutique system of magic. The slave would be the only one who ever knew the name of the god, at least in theory, and so history tells us they were either rewarded with lives of luxury to keep them in line or were killed so that none could remember the name of the gods and therefore threaten imperial control over the magic. How exactly they were formed is list to time, but that they existed is fact.

Initiation into these schools did not come cheaply, or easily. What history remains of these schools tells us that while one could learn the theory of the magic as one would study any theoretical art, to be an actual practitioner required one to have their soul imbued with the domain of the specific college they were under.

Oration

Unlike all the other four major schools of magic, Orators did not have their souls imbued with any particular domain of magic. Indeed, their most celebrated practitioners tended to have no soul at all. Oration was the purest and least orthodox form of Empyrean magic, based around a theory that if they could learn the true names of inanimate objects they would be able to mold and shape the world like the Hours did. History tells us that this theory was never proven one way or another, as charlatans on behalf of the School of Oration would try to show the true power of their magic, only to be proven wrong later.

What is true is that their repository of true names and ability to find them made them a powerful force. People feared the power of the Orators in this regard. The School of Oration would actively seek out any soulless they could find, and controlled who these practitioners could marry in order to keep their bloodline from developing a soul.

Necromancy

The College of Necromancy dealt mostly with the newly dead and weak spirits. Their art was sometimes used to heal the impossible, restoring the dead to life. Other uses included just speaking to the dead, or for those necromancers with a soul, outright walking through the Halls of the Dead.

Binding

The College of Binding invented the creation of Deiforms. They conjured gods, ancient humanity, beings with powerful souls. They would use the true name of a spirit in order to bind it to their will, and without ever casting magic themselves force the spirit they bound to act on their behalf. Most Binders were accomplished Necromancers in their own right, though there were some who specialized exclusively in Binding.

It is said that a Binder was either humble, or young. No arrogant binders survived into old age.

Life

Of all the schools of Empyrean magic, the School of Life is the one whose practitioners all definitely died long ago. The discovery of this magic involved forcing Makers into slavery, and then forcing those slaves to imbue humans with the intrinsic power of their magic. An elven plot was hatched after the discovery of this magic was made known. They stole the school's book of names, and using the true names inside the book systematically killed every living practitioner even before the Empyrean Empire fell.

Almost nothing is known of it beside for some of the story of its origins, and that it once existed.

Change

Of all the five schools, the School of Change had the most colleges. It is said that at its height, half of all wizards in the Imperium were Changers. How many colleges there were, and what those colleges specialized in, has been lost to history. Do not consider this a complete list.

Living

Grafting is not a true magic, but its study began under the wizards of The College of Living Change. Grafting is but a crude imitation of the magic that those wizards practiced. It is said that the magic lives on among the stars somewhere, as knowledge of the magic was once famously bartered away in exchange for an unknown reward with the denizen of a star known as Demigos.

Alchemy

Turning lead to gold, rendering steel as limp as a wet noodle, among other exploits. Modern alchemists, like grafters, owe their origins to students of this particular college. It is rumored that the College of Alchemy never truly gained complete control over their patron, as they merely used its power as a catalyst for other processes.

Passageways

The School of Passageways dealt mainly with portals, as well as traveling through the Unseen, and - supposedly - to other worlds entirely. It is known that most of their magic dealt with projecting, that is, leaving their body behind and exploring a place with their disembodied soul instead. The school also explored magics that rendered a physical body superfluous: telepathy so that they amay speak without a mouth, telekenesis so they could move objects without hands, and so on.

Knock

The College of Knock dealt mostly with bypassing barriers to their exploration. Usually this came in the form of magical defences that they would then have to break.

Seals

In constant competition with the College of Knock, the College of Seals dealt with the opposite. Protecting the empire from supernatural threats by the creation of impenetrable magical seals.

Obliteration

The School of Obliteration enjoyed a great deal of imperial preference. It dealt mostly with war, and many of its professors also served as officers in the imperial legions, or vice versa.

Fire

Burning. Death.

Banishment

The College of Banishment dealt with banishing spirits back to the Unseen, and what other magics later developed from that original magic's practical application.

Artillery

Of all the colleges of all the Empire's schools, only the College of Artillery survived the end of the empire. It remains alive and well, if much diminished, in Westfal. Not coincidentally, it was the only College that headquartered itself in the empire's former colony.

Runic Magic

Each Hour is associated with one or more runes. When the symbol of a rune is invoked, and imbued with the power of the invoker's soul, a magical effect happens depending on what the rune in question does.

The casting of runic magic takes more power than it should. When one attempts to cast it, one soul's worth of energy always seems to disappear into the aether, not affecting the spell. Meaning that it is impossible to cast for anyone who does not already possess two souls worth of capacity.

Runic magic does not need to be attuned.

Sigils

A sigil is a rune that has been carved, painted, or otherwise imposed onto the surface of a thing. This can be in the form of a tattoo on the body of a mage, just as well as it could be a sigil engraved on a ring, or carved on a paving stone. It doesn't matter where the sigil is or what material it is on, as long as the sigil is legible.

If the sigil is carved correctly.

If the sigil is empowered by more than four souls, it must be contained within a symbol that corresponds to the maximum number of souls it can contain. Such as a pentagram, hexagram, etc. The exact number, if it corresponds with an Hour, can also influence what Hours are being invoked. The most powerful sigils are encased by a simple circle.

Gestures

Beside for sigils, gestures are the other way that runic magic is cast. One is able to make gestures with their hands that correspond with the runes in question, and in so doing produce a magical effect. Typically, the tips of fingertips or the knuckles of the hand align to form the points of a rune to be able to make the appropriate gesture.

Casting Runic Magic

Once a rune or series of runes have been produced by gesture, the mage must imbue the rune with power. If the caster is invoking multiple runes at once, they will produce a more complex effect. If instead the mage is activating a sigil, the sigil must already be imbued with sufficient power for the spell to go off or else the sigil will simply not function.

The order in which Hours are evoked matters. If an Hour is invoked in the wrong sequence, or with Hours who are not compatible with them, the effect of the spell may change. Up to and including the death of the mage attempting to conjure them, in retribution for the mage's ignorance.