Magic
Magic in Getha stems from quintessence, which is a naturally occurring fifth element and the "blood" of El, the World Dragon. It is also called the "blood" of the soul. Every living being has a soul and thus quintessence, but not all can use it to make magic. The majority of sentients have no arcane ability at all. Of the magically-inclined, most are restricted to the most basic spell-casting (orbs of light, small gusts of wind, a minor hex to make someone stub their toe). Only a minority of spellcasters can wield more powerful and more complex spells.
The reason for this is that there is a limited amount of environmental quintessence that can be used by sentients. This source can only be used for very basic spells, as there is usually not much of it in any given area (there are exceptions; see below). More complex and powerful spells require the quintessence of the caster. However, soul quintessence can be quickly depleted by untrained casters. This depletion (a bleeding out of the soul) results in death, sometimes explosively depending on the speed of depletion and the nature of the magic being cast.
This use of quintessence is the Flow, as the quintessence flows out of the caster (it also flows from El). This supply replenishes naturally except in very rare cases.
There is a much rarer use of quintessence called the Ebb, which brings quintessence into the caster (and into El). This use is conducive to casters who make thralls or minions, particularly undead ones. The Ebb of quintessence into the caster makes a connection with the subject, either controlling their mind or causing a dead body to rise again. Note: undead seek out sources of quintessence, usually from living beings. Mages are particularly attractive to undead.
The Flow and Ebb and mutually exclusive. A caster cannot use both at the same time, as one is disruptive to the other. Any attempt results in a very nasty death. Most casters can only use one or the other exclusively, though legends speak of exalted dragons that could use both.
It is possible for an area to gain an unnatural amount of environmental quintessence. Casters can access more power (at risk for the untrained) from these nodes. Most nodes are Flow oriented, but occasionally Ebb nodes form (particularly in high magic use areas). Masterless undead or other mindless creatures can be found near these nodes. These minions attack living creatures to draw out the being's quintessence to "feed" the node. Both kinds of nodes can spontaneously appear or disappear.
With the proper preparation quintessence can be gathered and stored in various kinds of foci such as physical objects (mirrors, gems, etc) or drawn objects such as circles or arrays (circles tend to contain or exclude, arrays are built for a specific purpose). Foci are also used in the management of quintessence currents, usually in the form of spoken incantations (prayers, song, chant, even instrument music).
Exalted and risen dragons can use much more quintessence to much more effect due to the powerful nature of their souls, especially the exalted. To use an analogy, humans and the like are planets, and exalted dragons are suns. There are a few odd exceptions that stemmed from unusual circumstances.
Orders of magic casters were founded to pool knowledge and teach. However they tended to be very exclusive. After the Queensfall, universities opened up schools for teaching the arcane arts to those of lesser power or means.
These days talk of magic is disdained, as it appears that no one can use it any more. Many think that stories of magic were all exaggeration.
