Some form of magic features in every fantasy novel ever written.
It’s practically one of the requirements that are needed to turn your average story into a fantasy story. Sadly this is something many authors tend to mess up. Even fantasy stories that started out good go downhill due to bad magic management. You could say magic is as important as the world map of your story, especially where the plot is concerned.
Fantasy worlds are usually split into two categories according to the magic present in them. High magic and low magic.
High magic worlds have magic all over the place. Examples include the ‘Wheel of Time’ world created by Robert Jordan. Magic in a world like this is common and very visible. Whereas Low Magic worlds don’t have as much magic, it might even be only rumor and children’s stories, the truth known to and practiced only by a few individuals. The most famous example is the world of Westeros created by George R R Martin. This categorization should be considered when answering a very important question. How much magic should you include in your world?
You should also stick to the amount you decide.
When determining the Magic Level of your story. You should think about what the consequences will be down the line. A high magic world will use magic to solve most mundane problems. For example fighting, transport, communication and healing. While this might be extremely helpful in moving the plot right along and keeping the focus on the characters, it might just as easily be a choice you regret later on.
For example in a high magic world, the heroes don’t need to make a hair raising journey to warn the neighboring kingdom of the impending invasion, they can just communicate it telepathically. Your main character need not risk life and limb to make a thousand mile journey across the continent, they can just teleport. They don’t need to suffer crippling injuries, a wave of a wand and they are healed. You can see how it can be useful. But you also need to see that this kind of magic system can get out of hand very quickly. For one, you need to be fair in your magic use, it can’t be just the hero who can teleport all over the place, the villains must also have the same abilities, usually more. They don’t need to waste their armies pounding against the walls of a city, they can just teleport in and unleash magical destruction. The story, the entire plot, can change with heavy magic use among the characters.
The opposite of this is the low magic world, where magic is a rare commodity and definitely not everyday fare. It might be used for momentous events like the assassination of a king, but never in lieu of a mobile phone. Having a low magic world also opens up many more plotlines and character development. An injury might be crippling and how the character deals with it is going to be interesting to see. A journey might take a long time and introduce us to large parts of the world the story takes place in. You don’t have the option of taking the easy way out, but you have many more options of where to take your story.
The other thing authors tend to forget is that you need to stick to your magic level.
For an author, having magic in their story is like having a huge pile of chocolate in the fridge. You need to constantly resit temptation. You might be tempted to find a magical solution for every little problem your hero comes across, and this is well and good, but remember that this will end up making the hero dependent on magic to get the job done. The reader might as well get enamored with your magic system and ignore the hero entirely. It becomes worse if you have your characters conveniently discover new and heretofore undiscovered magic every time they encounter a seemingly impossible problem. Once or twice can be called a plot twist, but more than that it turns into ass-pull.
Authors like Christoper Paolini and Robert Jordan are especially guilty of this, by the end of their stories the magic system was mutated beyond all recognition and they were pulling magical solutions for every little problem their characters encountered.
Remember, keep your magic level constant, keep the ass-pulls at a minimum.
A character who uses their wits and guts to solve problems is actually much more attractive than a magic junkie. Remember Bilbo Baggins went toe to toe with a dragon in a riddle contest. In my opinion it was one of the best scenes of fantasy.
Magical training is another point authors love to cheat on. Especially when they start with a hero with a farm village background who can barely read. By the end of the story they are tossing magic around with the best of them. Even against characters who had studied magic for decades. Remember that Hogwarts needed seven years to turn Harry into a passable wizard. If magic takes decades to learn, then it should take decades to learn, one character alone shouldn’t get accelerated training.
Also please don’t suddenly turn your story into a high school drama by sending your character into a magic school halfway through a sweeping epic. This happens far too often in fantasy novels. School stories are fun, especially if you are learning magic, but you shouldn’t take time off from the main plot to write it.
One of the best magical training scenes I’ve read is done by Ursula K Le Guin in ‘A Wizard of Earthsea’. The main character spent years learning magic, by the time he went to the school he had already learned from two teachers. Training took time, it was the main focus of the character, it wasn’t a side quest. Patrick Rothfuss does another great example in ‘The Name of the Wind’. The main character was trained in magic for years. He is portrayed as extremely intelligent and even then has to work hard to master magic at a university.
I believe that most authors end up with these kinds of stories because of lack of planning. They create a magic rich world and throw a farm boy hero against it. Eventually they write themselves into a corner and find that said farm boy really needs a power up to keep up with the rest of the magic user characters and confront the villain. So they start to apply quick fixes to the plot. The second book of the Inheritance Cycle had a very long training montage, and a literal level up. All so the main character could keep up with the newly revealed villains (and their magic). The Wheel of Time series also has examples for all of the above. The hero gets ancestral memories telling him how to use magic all of a sudden. The obligatory school montage turns village girls into capable magic users in a very short time. And the entire magic system is turned on it’s head halfway through the series. You can barely recognize the series at the end.
Most of these can be avoided by careful plot planning and detailed worldbuilding. It might even result in a better story.
It isn’t easy to write magic into a fantasy story. But as it’s what puts the fantasy in the fantasy novel, it should be something an author thinks carefully about.