[quote=@BurningCold]
[@TheUnknowable] I'm a bit confused as to what any of the magics other than elemental even do. You describe how each magic is learned but I have no idea how to differentiate arcane from shamanistic from divine from demonic. I'd appreciate an explanation of this before I go forward in making my character.
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It's king of hard to explain but I'll try.

Arcane is essentially science combined with your understanding of magic (the arcane), which lets you manipulate the thing directly.  It can do anything, but because you have to have an academic understanding of the subject and the strength is dependent on that understanding, it's generally weaker than the other forms.

Shamanistic is similar in that it is based on an understanding of magic, but it specifically deals with the magic in nature.  It doesn't work with artificial things, such as machines, and doesn't adapt to "civilized" life very well either, as civilization is essentially the act of bending nature to the will of the people.  Because it deals with nature, it's stronger with magic that involves manipulating life and the natural world in ways which emulate natural processes, but is limited to things which the shaman has witnessed in nature and has gained an understanding of.

Demonic is granted by demons and evil beings/gods.  It generally is tied to a specific demon or evil deity and granted for devotion to them, and emulates their abilities and magic.

Divine is granted by good gods/angelic beings.  It generally is tied to a specific one, granted for devotion to them, and emulates their abilities and magic.

As an example, let's take fire magic.  Arcane mages would have to learn what causes fire and would either have to accelerate the oxidation of flammable materials or concentrate/generate heat, possibly their own body heat, to make it.  Elemental would just store elemental fire and control it.  Shamanism would have to emulate fire in nature, such as the result of a lightning strike or lava, though it would be pretty different from other types of fire magic.  Divine or demonic would be granted by a deity or demon with fire powers, and could work many different ways depending on the god/demon.