When it comes to magic and magic-equivalent effects in fantasy games, there are three general categories that we can divide up the effects between: arcane, divine, and psionic. We're going to look at these three categories and examine what makes them different and special, and what they all have in common.
Arcane Magic:
Arcane magic is manipulated by wielder, who has the abilities to do so through luck, skill or study. Where the ability to wield arcane magic comes from skill and/or study, there is no theoretical limit to what may accomplished through the magical effects if there is sufficient magical energy that can be gathered. Arcane magic is almost exclusively cast on an individual basis, though multiple casters can gather to enhance the effects of others through various arts.
The Strengths:
Arcane magic has no real limits to what it can accomplish except what the wielder can imagine and form clearly in their mind, making arcane magic highly rewarding to those who plan things out in detail. The versatility of arcane magic is also highly desirable, as its effects may stretch into any field that the proper studies extend into.
The Weaknesses:
The only hard and fast limitation on arcane magic is the mind of the wielder and what they understand and what they know. The general inability of arcane magic to heal natural, living things comes from an inability to understand the nature of those living things. Similarly, the inability to teleport into unknown locales comes from a lack of knowledge with where they are going.
Overall:
Arcane magic has a lot of balancing aspects, and for the right character can be highly rewarding.
Divine Magic:
Divine magic is magic in which spells and powers are granted from a powerful entity to a less powerful one. Despite the name, the source of the powers can be quite unholy, or the spells could theoretically be granted by a being who became very powerful through the use of arcane magic. The power is granted to the wielder, who then holds onto it until such a time as that power is released by the casting of a divine spell.
Some theorize that the casting of a divine spell is in fact only the final part of the spell's casting and that the act of casting the spell does not release the magical energies so much as it completes them. If this is the case, it would prove a striking difference between divine and arcane magic, as well as a concrete reason for the capabilities of divine magic which arcane magic has yet to duplicate.
The Strengths:
Generally speaking, divine magic is capable of attaining effects far greater and stronger than those that can be achieved by most wielders of arcane magic, due to the greater power and understanding of the entity granting the spells. The effects of divine magic can duplicate those of arcane magic, depending on the source of the power.
The Weaknesses:
The wielder of the magic is unlikely to have control of what exactly they are granted and capable of doing - the one granting them the magic has an agenda of their own, and would not empower the wielder to move against it.
Overall:
The outside constraints of divine magic placed on the wielder balance out the greater power and capabilities available through divine magic. The cooperative nature of the magic, however, will hinder anyone who tries to wield it without sharing a common goal with the one granting the power.
Psionic Effects:
Psionic effects are achieved through willpower and thought alone. Whether these abilities are born out of physiological capabilities or training and harnessing of the mind is a matter of some debate, but the effects are the same: thought alters reality.
Unlike arcane and divine magic, psionics do not rely on external power resevoirs which are shaped and molded to achieve the desired result, but instead psionics represent the channeling of internal strength and power.
If psionic capabilities are a result of physiology, this would mark an additional difference between psionics and arcane and divine magic, as well as hint at a facet of reality we had not previously considered.
The Strengths::
The inner nature of psionic effects allows the art to be applied without having to draw on an external reservoir of power, either in the form of a cooperative entity or raw magical energies waiting to be shaped.
The Weaknesses:
The internal nature of psionics places a practical limit on the capabilities of the art, as there is a definite limit on the power reservoir.
Overall:
Psionics are rather unique when compared to arcane or divine magic, making it a truly different path to different powers and abilities than can be achieved through ordinary magic.
