Magic in the Brass Realms

"The Powers of creation at my fingertips! I am unstoppable!"

— Arch-mage Ancano, shortly before his death due to Aether-overload

This article exists to serve as a guideline what Magic in the brass realms is.
Essentially magic is the ability to utilize exotic energies originating from the Spirit World to change the physical world.
All magic originates from spirits or the spirit world in some way, directly or indirectly.
Magic is very powerful but always comes at a heavy price.

For more information on the distinct 'schools' of magic go Here.

Magical reserves and potential

Before any mortal creature can learn to cast spells they first need the ability to use the various exotic energies stemming from the Spirit World. Wether they store some amount of it inside their bodies or can draw upon and channel these powers, the end effect is the same.

Conservation of energy:
Energy needs to be maintained, a magic user cannot expend a miniscule amount of his own energy to create a great conflagration of heat. He needs to expend as much energy as he creates in the world. While the amount of energy a magic user can store or channel vary greatly and is not easily measured, this founding principle puts a limit on the ambitions of many aspiring magic users.

Depletion and Exhaustion
Magic users can only cast a certain amount of spells before they need to rest and recuperate. Be it because they collect a reservoir of power that they expend or they exhaust their ability to act as a conduit for a time, they are all limited and can not operate at their maximum output for long.
It is possible to exhaust a magic user, leaving them totally helpless until they rest and recover.

Precision and Control

Fundamentally magic is about control. The more trained a magic user is, the higher their level of control the less of their power they will expend on their spells and the more powerful their spells will be.
A fire-priests flames will burn hotter, a sorcerer's telekinetik spells will be stronger and more efficient and so on.

However all magic users are highly vulnerable to having their concentration disrupted. They also need to be able to move their arms and hands freely in order to accurately guide their powers. [Br] Magic users, as a general rule, have problems performing while being punched in the face.

Magical Foci
All magic users need magical foci to cast their spells, without them they are near-helpless. Casting a spell without a magical focus is an order of magnitude more expensive and difficult as the focus essentially drastically increases the user's control over their own magic
Magical foci might be things such as wands or staves, but also holy symbols or ritual implements depending on the magic user and the school they practise.

Range Limitations
Control decreases with distance. As a result the power costs increase exponentially and magic is easiest in short range. That is why a fire priest will throw a fireball rather than simply making it appear atop the enemy and why you cannot do delicate magic at great distance.

Living Beings & Magic resistance
Living beings are not the same as inanimate objects. Affecting another's body with magic is extremely difficult and costly, affecting prostetics, clothing or piercings are somewhat easier and held objects easier still.
The determining factor is lifeforce or presence of soul, meaning even golems, spirits or plants work the same way.
Boiling somebody's bloos is ruinously difficult and exhausting, cooking the air near them is easier and lobbing an orb of fire at them is easier still.
Some creatures are especially resistant, such as ogres or Dragons, essentially amplifying this effect even more.

Miscellaneous

Magical creatures

There is many creatures, such as for example Dragons, that naturally draw on various forms of power. Many creatures instinctively draw on these energies, in a way that would take a human decades to learn if they were ever able to learn it at all. With especially potent creatures the various magical energies flow through their flesh and bones to such an extent that it remains attracted to the materials long after the creature has died.

Magical Materials

Be it rare plants or magical materials such as Riftstone, there is materials that form only under certain circumstances and are capable of drawing on sources of power as part of their material properties. Such materials can be used for a variety of things, mostly for the creation of Magic Items.

Magic items

Magic Items can be made from a variety of materials and drawing upon a variety of powers.
Created by any kind of magic user, these valuable object can be enchanted weapons or holy artifacts, potions of healing, artificial lifeforms or other exotic curiosities. Either way they draw upon their assigned source of power to create various magical effects. Magic items can lose their magic over time as the item degrades.