Magic systems are often seen as a crucial literary device. In High Fantasy, magic can permeate every facet within a society, while in Low Fantasy it may be less prevalent.
A magic system is a set of rules that regulate the magical effects that can be produced within fantasy settings.
Magic systems in fantasy can usually be categorised in one of two types: hard magic and soft magic. These terms were made popular by fantasy and sci-fi writer, Brandon Sanderson, who is well known for his hard magic system.
A hard magic system can loosely be described as a magic system with lots of rules and limitations which are expressly known to the reader. Soft magic systems have a greater air of mystery. The limitations of magic are not normally known, or at least not the point of view character, and thus also the reader.
Everyone creates magic systems differently, and this is by no means the only way to do so. Below is just my step-by-step approach on how to create a magic system:-
Step # 1: Define the Powers within the Magic System
What can people with magic actually do? Are your powers based around the elements? Are they more mental based powers? Or perhaps the powers are nothing particularly flashy at first sight, such as immortality. You wouldn’t even know you had magic for quite some time if that were your power. For a more thorough list of powers check out the Powerlistings Wiki.
Alsom consider how people with magic summon their magic. Do they need a wand? A magic artefact? The blood of their enemies?
Step # 2: Establish the Limitations Writing Magic Systems
What can magic NOT do? Does magic have a cost? Take note that where a magic system is greatly limited, the less costly it needs to be in order to be believable. Alternatively if the cost of magic is very steep, you don’t need to limit the power too much. Try to be more unique than having fatigue as a cost of using magic. It is an overused trope.
Step # 3 Identify Who Has Access to Magic
Perhaps magic only runs through the veins of certain bloodlines and therefore is unique to only a few select groups of people. Or perhaps magic is so commonplace, almost everyone has it to some degree. Perhaps only certain races like elves or fey have it, or perhaps only those of a certain age can make use of magic.
Step # 4 Explore Where Magic Originates From
Perhaps magic is divine in nature and originates from gods, or perhaps it is evil in nature and originates from demons or dark elves.
If magic is only found in a certain location, perhaps it can be captured in special stones or artefacts.
If magic can be harvested in such a way, either from a magical location, or from people, also think of the ramifications to what happens to that location or person once drained of magic.
Step # 5 Consider How Magic Affects the World Around It
Is magic accepted in your story, or is it forbidden? What do they do to people who exhibit forbidden powers? Perhaps like in Fox’s The Gifted (a TV show exploring an alternative X-Men timeline) people who demonstrate dangerous powers are locked away in prisons or forced to use their powers to take out other dangerous magic users.
Or perhaps magic is widely accepted and fully integrated into everyday life. In The Legend of Korra, lightning bending (a specialisation of fire bending) is used to create power as electricity.
Remember that not everyone uses magic the same way. People are different and even those with the same powers may see things from a unique perspective.