How to Create a Believable Magic System in Your Fantasy Story

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Today’s post is by developmental editor and book coach Hannah Kate Kelley.

What is a magic system?

A magic system is a map establishing where magic comes from and how it works. It contains a structured set of rules and principles of magical powers in a work of fiction.

Like geography, historical era, and social customs, a magic system is another element of world building. More often than not, your story will employ magic as an agent to instill conflict and drive the narrative forward—and it’s the system that keeps everything organized for both the writer and their readers.

When the young witch Hermione Granger magically lifts her feather in her Hogwart’s Charms class before her friend Ron Weasley can, chiding, “It’s Leviosa not Leviosaaa,” readers understand the scene’s humor. Why? Because author J.K. Rowling has already established a magic system with clear rules. In order to do the levitation spell, the young witches and wizards must pronounce the incantation correctly, which Ron obviously hasn’t mastered yet. Without a magic system in place, this scene would have fallen flat.

Besides the magical world of the Harry Potter series, here are a few more fiction novels and series featuring magic systems:

Fourth Wing by Rebecca YarrosHuntress by Malinda LoMexican Gothic by Sylivia Moreno-GarciaThe Gilded Ones by Namina FornaThe Invisible Life of Addie LaRue by Victoria SchwabThe Lord of the Rings by J.R.R. TolkeinThe Night Circus by Erin MorgensternShadow and Bone by Leigh BardugoWhat makes a magic system believable?

Believability keeps readers immersed. If your readers aren’t engaged with your story’s world, they are more likely to get their DNF (did not finish) stamps out. The more logical your magic system, the more readers can suspend their disbelief.

Before we dive into how to make your own magic system, let’s explore the two most common magic system pitfalls to watch out for:

1. An overly complicated magic system that overshadows the plot

While worldbuilding is a huge draw, your character development and plot should actually take center stage. A complicated magic system often means an overpowering one because readers are spending more time trying to understand your magic system, and not enough time invested in the story.

How do you know if your magic system is complicated? Your best bet is to ask readers—whether that’s an editor, beta reader, or trusted friend. While many readers love in-depth magic systems, if they feel confused or are constantly reviewing details from a previous chapter, it’s time to simplify it.

If you find your magic system is becoming overly complicated, here are a few tried and true fixes:

If one part of your magic system is complex, simplify the other parts. For example, if you have a significant number of magical abilities, simplify the rest of the magic system by giving every ability the same harnessing process.Similarly, if your plot is already complex, keep the magic system simple. A common example of an overcomplicated magic system is one with an excessive number of branches or schools, each with its own unique rules, tools, incantations, and rituals; a dozen different kinds of magic, each requiring specific spell ingredients, incantations in different languages, and physical gestures that vary by moon phase. On top of all that, let’s say you also have 82 different magic beasts. And your plot is complex. Balance the scales by either simplifying the plot and/or the magic system.If two or more creatures, magical abilities or other magical elements serve the same plot purpose, try conflating them. Let’s say your story has sixteen different creatures that attack the protagonist in Book 1, each with their own origin story, abilities, and magic source. While this diversity might feel more realistic, sixteen different beasts is a lot for readers to keep track of. Condensing the creatures into only four or so different types, with a hierarchy of how dangerous their abilities are, will be far easier to follow.Dole out your magical world in waves, just as J.K. Rowling does between Harry Potter and the Sorcerer’s Stone (Book 1) and Harry Potter and the Deathly Hallows (Book 7). Though Harry doesn’t discover the horcrux magic until the later books, there are other types of magic to keep readers engaged, as well as well-paced clues pointing to the horcrux magic. Readers slowly build up their understanding, no overloading.

Complex doesn’t mean complicated. A good magic system is simple, made richer when the same principles apply to different characters. Think of a good magic system as an expansion of one central idea, rather than a messy exploration of several ideas. And remember to balance your magic system with the plot itself.

2. An inconsistent magic system

New fantasy writers break this rule all the time, whether it’s for an exciting plot twist or to fix a plot hole you accidentally created back in Book 2. A common example is when, early in the story, a character is said to need a specific incantation to cast a spell. Later, they cast the same spell with just a thought, without any explanation for the change.

Similarly, fantasy writers don’t want magic to serve as an all-too-convenient deus ex machina plot device to solve story issues arbitrarily. Say a previously unmentioned magical artifact appears just in time to solve a major problem during the story’s crisis, with no prior foreshadowing or explanation. That’s an inconsistency that will leave readers confused and frustrated.

What’s the fix for an inconsistent magic system? First, establish your magic system with care. And second, stay organized by referencing your established magic system often and updating it if you decide to make a change.

Now that you know the two common pitfalls to avoid, it’s time to create your magic system.

Define the role of magic in your story

Your magic system needs to operate seamlessly within the tale you plan to tell, not the other way around. That’s why the first step is to establish what role magic will play in your story. Will magic control a society? Or will it just exist in the backstory, in a world where magic is newly eradicated?

Sure, you could throw magic into any story, but unless it plays an important part of the plot and character development, you might be better off writing sci-fi or another genre. Imagine if The Great Gatsby by F. Scott Fitzgerald had a league of magicians tossed into the book. Given that the story is a realistic social critique of 1920s America, this magical inclusion would obscure the point. Magic doesn’t fit into this story. Whereas, in Shadow and Bone by Leigh Bardugo, mapmaker Alina Starkov’s discovery of her latent magic not only changes her trajectory, but also plays a large role in her self-acceptance, romantic tensions, and ethical dilemmas. Magic fits in this story.

Define magic’s role in society:How does magic fit into your world’s history, culture, and everyday life?How does each society in your world regard magic? Do they hold magic in contempt, fear, adoration, or are they oblivious to its existence?How does each society use magic, if different from one another? Are societies separated by geography, class, gender, and/or magic-users and non-magic-users? How does the presence or absence of magic affect social hierarchies?Define magic’s role in the plot:How does magic directly influence the plot and main character development? How does it indirectly influence these aspects?How does your protagonist’s abilities or lack thereof influence their internal conflict and/or the central theme?Does the general storyline function perfectly well without magic? If so, are you interested enough in writing a magic system regardless?

These questions will help you decide whether it makes sense to include magic in your story or not, and if so, what role magic will play.

Research your genre and subgenre

If you plan to publish your story, the next step is to do a little bit of homework on your story’s subgenre because many of them feature magic in different ways. Understanding genre conventions is all about meeting reader expectations. Some magical tropes you’ll use and others you won’t, or you’ll put your own spin on them, but either way, you need to be aware of them.

The genre conventions surrounding magic look vastly different between a gothic horror story like Mexican Gothic by Silvia Moreno-Garcia compared to the cozy, low-stakes medieval fantasy Legends and Lattes by Travis Baldree. The former uses more ambiguity around the magic’s source, as is typical of the creeping suspense found in gothic horror, while the latter book plays off a D&D-based realm in which magic deeply integrates into everyday life.

Doing this research can also help writers avoid tired tropes and harmful stereotypes. For example, if year after year, all readers get are werewolf stories depicting the “special” or most dominant werewolf with pristine white fur, consider why writers regard the color white as such a predominant signifier of importance and how you can switch it up.

Study 4–5 comparable book summaries or reviews in your subgenre, preferably published in the past two years. If you’re not sure which subgenre you’re writing, this is a good time to uncover that by exploring what subgenres are out there.

While researching each book, ask yourself:

What roles does magic play in this story?Do the protagonists have magical abilities or not? Do the antagonists? Which traits do the main characters possess?What kind of magic exists in this world? How do magic users, if there are any, use the magic? What do they use the magic for?Is magic explicitly stated and understood, or more abstractly understood?Do the societies within the story accept, reject, or remain unaware of the magic surrounding them?What do readers think of the magic system in this story? Are they excited by or annoyed by any tropes?

At the end of your research, you’ll understand your subgenre’s most prevalent magic tropes and conventions so you can both play into and subvert them as you see fit. Whether you choose to publish traditionally or self-publish, your agent, editor, and readers will be glad you did your homework.

Choose a magic system type

Now that you know the role magic will play in your story, as well as how it will fit into your subgenre conventions, it’s time to narrow down the type of magic system you want to use: hard or soft.

Hard magic systems

These systems are characterized by well-defined rules and limitations where the rules are clearly explained and magic functions predictably.

Writers of high, epic, and urban fantasy subgenres enjoy hard systems because the cast of characters and their various plotlines can be very expansive, and therefore easier to track with a concrete navigation. Hard magic systems can also lead to clever problem-solving scenarios where characters use their knowledge of these rules to overcome obstacles.

In Children of Blood and Bone by Tomi Adeyemi, the magic system is rooted in the ten Maji clans, each one able to harness an element of nature (e.g., controlling water, communicating with the dead, and healing). The magic source, known as Ashê, comes from the Maji’s blood. The story provides clear rules about how magic is accessed and used, and there is still room for mysterious and developing elements as the characters discover their powers.In Shadow and Bone by Leigh Bardugo, the Grisha magic (also known as Small Science) has clear categories and rules, with practitioners able to manipulate specific elements like darkness, sun, air, blood, and metal, as well as three orders of classification: Corporalki, Etherealki, and Materialki. Within the Grisha’s clear-cut magic system, the sudden emergence of a Sun Summoner (which the protagonist Alina Starkov turns out to be) is a thrilling phenomenon because everyone is already aware of the legends and the potential impact such a power could have.Soft magic systems

Soft magic systems are more mysterious because they are less defined than their harder counterparts. The rules governing the magic are not fully explained, which can create a sense of wonder, suspense, and unpredictability. In these systems, magic often serves as a plot device or an atmospheric element rather than a tool for problem-solving.

This type of magic system is a good fit for subgenres that lean into the abstract, like magical realism, gothic horror, and supernatural fiction.

Writing soft systems can be trickier, because writers must balance clarity and consistency alongside ambiguity. Some writers accomplish this balance by revealing the source of creeping magic by the midpoint or ever later, while other writers only offer speculation on the source but are clear about how the magic can and cannot be used.

In The Invisible Life of Addie LaRue by V. E. Schwab, the central magical element—a deal with a god-like entity allowing Addie to live forever but be forgotten by everyone she meets—is not clearly explained in terms of rules or mechanics. Readers simply accept the fact that the god can manipulate magic, though the limitations become more clearly defined as Addie actively tries to find a loophole in their deal. The story focuses more on the existential and emotional implications of this magic than on the detailed inner workings.In Mexican Gothic by Silvia Moreno-Garcia, as well as many other gothic horror novels, the magic source comes from the sprawling, fungus-infested estate itself as it threatens to trap her forever. Because the protagonist Noemí Taboada doesn’t initially understand where the magic is coming from, whether or not it is real, or what it has planned for her fate, the magic feels eerie and atmospheric, creating a sense of dread and wonder rather than explaining the mechanics of the supernatural happenings.

The better suited your magic system to your story, the more believable it will be. Using your understanding of your magic’s role and subgenre conventions, choose either a hard or soft magic system before you iron out the details in the next and final step.

Creating a believable magic system

Now you’re ready to put everything together and parse out your magic source, methods of use, visual and sensory details, rules and limitations, and magical character profiles.

Define the source(s) of magic

Where does magic come from in your world? While magic could come out of an object like the High Place mansion in Mexican Gothic, it could also stem from a genetic ability like the witches and wizards in the Harry Potter series (what a bummer for all the squibs or muggles). Other sources include elemental/natural, divine, arcane, cosmic/celestial, blood magic, psychic mind reading, soul/spirit, and techno magic. If your magic system is abstract enough, a source may never be revealed, though it might help as the writer to have a general idea of the source.

Can you have more than one source of magic in your world? Yes, try keeping the other parts of your magic system tighter to maintain the balance between simplicity and complexity. And if you have more than one source, try introducing classifications and hierarchy. For example, in Shadow and Bone, the Corporalki Grisha manipulate the human body, the Etherealki Grisha manipulate natural elements, and the Materialki Grisha manipulate materials like metal, glass, and chemicals. A Corporalki Heartrender who can control the body is more powerful and feared than the undervalued, less-combative Durasts and Alkemi of the Materialki order.

No matter which source you choose or how many sources you choose, remember to select the best ones for your story’s unique plot and magic role.

Define how magic users harness magic

How do people wield, summon or otherwise use magic in your world? How magic users use their powers will depend on the source of their magic, and writers will likely need a different method of use for each source of magic. If you chose blood magic, for example, will they wield their ability through wands? Or perhaps spoken incantations, hand movements, spells, rituals, or touching certain artifacts? If you’re going for an abstract route, maybe they make deals with a devil or fall prey to curses?

Or come up with your own harnessing method. Though The Magicians book by Lev Grossman doesn’t feature intricate hand motions, the TV show rendition employs hand “tutting,” a type of dance where dancers create harsh geometric shapes with their bodies, in order to cast spells successfully. While this may not come across via written word as easily or interestingly as in the show, it’s a good example of an imaginative use method.

The key here is not only to keep it simple but also consistent. If a magic user harness magic in one way at the start of the book, they need to continue to harness it in the same way throughout the rest of the story, though it’s fine if significant practice makes the magic flow easier.

Define visual and sensory details

What does magic in your world feel, taste, smell, sound, and look like? Emphasizing the importance of descriptive details makes magic feel real to readers. A great example of this is The Night Circus, where the writer’s incredible detail captures each new tent’s magic as the two protagonists compete for the most impressive display of magic. Look at the author’s description of the circus clock, an important element in the story that sits atop the Night Circus:

The body of the clock, which has been methodically turning itself inside out and expanding, is now entirely subtle shades of white and grey. And it is not just pieces, it is figures and objects, perfectly carved flowers and planets and tiny books with actual paper pages that turn. There is a silver dragon that curls around part of the now visible clockwork, a tiny princess in a carved tower who paces in distress, awaiting an absent prince. Teapots that pour into teacups and minuscule curls of steam that rise from them as the seconds tick. Wrapped presents open. Small cats chase small dogs. An entire game of chess is played. […]

An entire game of chess! Though the clock is a fantastical element that could never exist, the description is so detailed and visceral that readers have an easier time suspending their disbelief. Aim to bring your audience the same amount of immersion by defining magic through all our senses.

Define clear rules and limitations

What can magic in your world do and not do? As we know, stories thrive on conflict, and your fantasy story can create a lot of rich tension by stacking rules and limitations on your magic users’ abilities. After all, which sounds more intriguing: an invincible protagonist whose magic reserves never tire, or a vulnerable protagonist who struggles with the limitations of their magic in the face of a powerful antagonist? Rules and limitations make for more plausible storytelling because our lives are full of them.

For each magical element and creature, be clear about the rules surrounding their abilities. For example, let’s say the magic users in your story can manipulate water. Can they manipulate the water at any time? Do they need to be near a source of water? If so, how close do they need to be? Can they manipulate blood and water? Do they tire after using their magic, or not?

Create magical beings profile(s)

What are the classifications, abilities, limitations, and physical descriptions of each magical being in your world? Create profiles for each creature. This will put everything in one tidy place, including their magic sources, use methods, abilities, and limitations. These profiles will keep your magic system organized, especially if you have more than one magical being with their own class or abilities. While you can get more detailed in your profiles, start by hashing out these important characteristics first:

Magical Creature or Being:Classification or Grouping (if applicable):Abilities:Limitations:Physical description or common traits:Next steps

By crafting a magic system that not only works within your story idea and subgenre, it will be believable enough to keep readers engaged. You’ve invested in your story by building up a simple, cohesive map of your magic. And your readers will thank you.