There was a time in the fantasy genre when magic was simply, er, magical, and didn’t require a whole lot of explanation.

But time has a habit of making everything more complex, and so it’s unsurprising that magic systems have followed suit. These days, there are basically two schools of thought when it comes to magic in books, as outlined in a widely circulated essay by author Brandon Sanderson concerning “hard” (rigorous adherence to rules) and “soft” (looser, more hand-wave-y) magic systems. It’s now possible to classify just about every fantasy book into one of those two categories, and many readers have some very strong opinions about which is preferable and why.

Of course, we’re advocates for an author choosing the type of magic system that best fits their narrative, but for purposes of classification, let’s imagine a scale of 1 to 10, where 1 indicates the least-rigorous kind of magic system (everything can be explained via the phrase “because magic”) and 10 is the most-rigorous (finishing a book or series in this category earns you an honorary doctorate in that magic system).

Here’s how we’d rank 16 fantasy books and series on our rigorous/non-rigorous scale—but before we dive in, let us note that we aren’t suggesting one type of magic system is better than another; storytellers should be allowed the latitude to cast their own spell over readers.

The Lord of the Rings, by J.R.R. Tolkien

Magic System Rating: 1 (Because Magic)

It’s difficult to have a conversation about classifying fantasy books without at least mentioning Tolkien. The man was writing a modern myth, and myths don’t usually explain their magic in great detail, so it’s little surprise that Tolkien’s magic displays very little that’s systematic in the modern sense. In Tolkien’s universe, magic stems from wisdom and inherent power—the closer you are to Iluvatar, the creator, the more inherent power you have. As a result, the elves and Istari are always more magically capable than men, and the eldest and wisest among them are the most powerful. But Tolkien also presents all power as inherently corrupting, and magic the most corrupting of all. In the end, despite the reams of detailed backstory, history, and character biography the man created, his magic has almost no rigor at all, rather originating from the individual will and knowledge of its practitioners.

A Song of Ice and Fire, by George R.R. Martin

Magic System Rating: 1 (Because Magic)

Martin is writing a purposeful deconstruction of epic fantasy tropes—including magic systems—and has actually put some work into making his magic frustrating and inconsistent beyond a few broad-stroke rules (there’s definitely some like-for-like business, with equivalent sacrifices needed to produce an effect). Most of the people actively using magic in his world seem befuddled by the whole process; the general sense is that it’s unreliable and often ineffective—but when it works, boy howdy does it ever work (shadow assassins, am I right?). It’s a fascinating twist on the whole concept, as its lack of rigor is intentional, and serves the larger design of the narrative—a design we must note is not yet complete, so there may be more to come on this front.

The Belgariad, by David Eddings and The Books of Earthsea, by Ursula K. Le Guin

Magic System Rating: 2 (Simple, but Effective)

These two mainstays of post-Tolkien fantasy offer a slight refinement on the “obscured by the mists of time” approach J.R.R. took, offering extremely simple magic systems that apply a very, very small instructional set. In Eddings’ old-school classic, certain folks can employ the Will and the Word—want something hard enough, and speak a word, and it happens (within some extremely broad limitations set by the gods). In Earthsea, everything has a secret, true name in the ancient language of the dragons; if you learn it, you have power over that thing or person (and by the way: you can’t lie in the dragons’ language—unless you are, in fact, a dragon). These rules are so basic as to allow for just about anything to happen, magic-wise, but they do offer at least a sketch of a system on which to hang your pointed, star-and-moon-covered conical hat.

The Eternal Champion, by Michael Moorcock

Magic System Rating: 3 (Non-Rigorous, but With an Explanation)

The legendary Moorcock also follows the old-school habit of not explaining his magic too deeply, but he does at least provide an explanation of how it works, along with a dose of unreliability. Most magic in his universe is accomplished by contacting, bargaining with, or summoning and controlling demons and elemental beings—if you’re looking to smash an advancing army, you could summon an incredibly powerful, army-smashing demon. The problem being that all these immensely powerful beings have their own agendas, so it’s not uncommon for these sorts of spells to go awry—or for someone to lose control of them entirely, resulting in chaos. It’s a neat way to cover for the fact that your magic system isn’t so much a system as a loose set of guidelines.

Shades of Magic, by V.E. Schwab

Magic System Rating: 4 (Mystery Box)

V.E. Schwab’s magic system in the excellent Shades of Magic series is organized, but not terribly rule-laden. We understand the mechanics of the wizard-like Antari’s blood magic, but much of the ways and hows of magic’s function in the three magical Londons (Red, White, and Black—Grey London is our London, and thus has no magic) is left mysterious. Not that this hurts the story in any way—Schwab expertly gives readers exactly enough information to make the system workable without overloading them with detail that, frankly, isn’t necessary to appreciate her story, and might even ruin the spell of awe and wonder cast by the character-centric narrative.

The Harry Potter series, by J.K. Rowling

Magic System Rating: 5 (Faux-Rigor)

Rowling’s omnipresence makes her an automatic reference in this discussion. Though they take place at a magic school, the magic system she’s developed for the Harry Potter universe isn’t actually all that rigorous. Magical ability is genetic, so you’re just sort of born with it, and behind all the words and wands there’s precious little explanation of exactly how it all works (although, to be fair, there’s a bit more detail when it comes to potions). Despite how much Rowling has added to the universe via Pottermore reveals and controversial tweetbombs, we’re still not clear whether you can just add the word maxima to any spell in order to increase its power.

Jonathan Strange and Mr. Norrell, by Susanna Clarke

Magic System Rating: 5 (Faux-Rigor)

Clarke also does a fantastic job of hiding a pretty vague magic system beneath a lot of superficial detail, lending an appearance of a complex set of rules governing the use of magic without ever offering a rational set of rules. Clarke isn’t floundering, though—one of the great qualities of the novel is the fact that the actual magicians in it are often just as befuddled by the details of magic. It makes sense, since in-narrative, it’s presented as a lost art, only suddenly returned to the world in the early 19th century. The combination of oddly specific spells (for example, one involving a mirror, some flowers, and a specific set of patterns) and unanswered questions (which flower?) creates its own sort of magic: the illusion of a detailed system.

The Wheel of Time, by Robert Jordan and Brandon Sanderson

Magic System Rating: 6 (Both Rigorous and Non-Rigorous)

The magic system in The Wheel of Time is often misunderstood, for two reasons: one, it’s purposefully obscured, in that many of the supposed rules are never explained and much of it is chalked up to innate skill and talent. Two, it starts off as a relatively rigorous system that then decays into something much softer as the plot points demanded it. The magic system is extremely consistent and pattern-based—once you know how to bend and twist a strand of the One Power to produce a certain effect, you can repeat the recipe over and over again with the same result—and the characters consistently work within those rules, and are often forced to be clever in using their knowledge in order to overcome obstacles (one of Sanderson’s own rules about hard magic). But an arms race of ever more powerful characters and plot twists that undermine the rules (Androl Genhald, your ears are burning) lowered the numerical ranking by a few points.

The Kingkiller Chronicle, by Patrick Rothfuss

Magic System Rating: 6 (Both Rigorous and Non-Rigorous)

The magic systems Rothfuss invents for his beloved epic fantasy are a curious hybrid. On the one hand, Sympathy—the linking of two objects so they share the effects of a single force—is extremely detailed, as are alchemy and other magics, to the point where Rothfuss says he has equations in his notes to back up every use of magic in the books. You don’t get much more rigorous than Sympathy. On the other hand, he also has a system of “true name”-style magic that is completely unexplained and non-rigorous. Rothfuss has explained that he simply wanted the best of both worlds: to give readers the satisfaction of understanding a magic system and appreciating its cleverness, combined with the sense of awe and wonder that unexplained magic can offer.

Tales of the Dying Earth, by Jack Vance

Magic System Rating: 7 (Rigorous)

There aren’t many SFF writers who have a whole style of magic named after them, but if you Google “Vancian Magic,” you’ll find your way to Vance’s Dying Earth cycle. Vance has a simple system: magic spells must be memorized, but they are fantastically long, so people can only memorize a few at a time—and spells are forgotten the moment you cast them. This kind of resource-limiting magic system is straightforward but adds that spice of limitation and obstacle that Sanderson codified in his essay. Vance doesn’t make any effort to explain precisely why magic works or how the spells are structured, which dings a few points on the rigor scale, but it’s a powerful idea that’s been borrowed by plenty of writers since.

The Broken Earth trilogy, by N.K. Jemisin

Magic System Rating: 7 (Rigorous)

No conversation about fantasy storytelling these days is complete without checking on what Jemisin’s doing—she’s hugely influential, highly successful, and what literary scientists classify as damn good. Her Broken Earth series creates a distinction between magic and what she terms orogeny; the latter is the ability by some in the seismically-unstable world of the Stillness to harness that seismic energy (and other forms of energy) and channelit as they will. Orogeny has plenty of defined rules that approach a scientific depth of complexity and rigor (the author worked with geologists to develop the science behind her magic), but Jemisin is famously disinterested in codifying her magic systems, and reacts humorously to any attempt to get her to offer a dissertation on the subject.

The Magicians, by Lev Grossman

Magic System Rating: 8 (It Eats Rigor for Breakfast)

As a deconstruction of Harry Potter, Grossman’s series would tend towards the rigorous side of the spectrum, wouldn’t it? Instead of a vague wand-and-word system that is more fun than sensible, Grossman explores what it might actually be like to study magic as a complex and ancient discipline. The spells are complex and follow specific patterns, require a lot of basic memorization and learning of fundamentals before you can skate off into theory, and the whole things feels like work the same way higher math feels like work. Yet the feeling that you too could cast spells if you just studied hard enough more than makes up for it.

Vita Nostra, by Marina and Sergey Dyachenko (translated by Julia Meitov Hersey)

Magic System Rating: 8 (It Eats Rigor for Breakfast)

Russian authors Marina and Sergey Dyachenko take a similar approach to Grossman’s The Magicians in sketching out the way magic works in their award-winning 2006 novel, which was finally released in the U.S. in 2018—though rather than mathematics, its rules veer closer to language theory and linguistics. When 16-year-old Sasha Samokhina enrolls at the Institute for Special Technologies, she is thrust into a magical education that couldn’t be any further removed from Hogwarts. In their first year, the students spend most of their time reading nigh-incomprehensible texts, training their brains to unlock the power inherent in language. Once they’ve mastered that (a process that literally transforms their brains), they develop more advanced abilities to manipulate the world through the definitional power of language. To say much more would steer us into spoiler territory; needless to say, you’ll finish the book feeling as if your own mind has been rewired.

Master of the Five Magics, by Lyndon Hardy

Magic System Rating: 8 (It Eats Rigor for Breakfast)

As the title suggests, there are five magical systems (at least initially) in Hardy’s 1980s classic, and they are all rigorously defined, with explicit rules and laws spelled out for you. The five magics are thaumaturgy, alchemy, magic, sorcery, and wizardry, and each discipline has its own set of rules. For example, the rules for wizardry, which is the magical discipline concerned with summoning demons, are The Law of Ubiquity (Flame permeates all) and The Law of Dichotomy (dominance or submission). In other words, you can summon demons through fire (fires built from different fuels will summon different or more powerful demons) and once a demon is summoned, the wizard must either dominate the demon’s will, or be dominated instead. Simple and elegant—and that’s most impressive is that Hardy developed these laws and rules for all five of his disciplines; he then goes on to illustrate additional meta-rules, applicable after his protagonist achieves the titular honor.

The Craft Sequence, by Max Gladstone

Magic System Rating: 9 (We Got Rules for Our Rules)

Gladstone true brilliance in this series is in his thinking about magic in terms of contracts and legalese, resulting in an extremely rigorous system that is also endlessly, infinitely flexible—just like real life contract law. Add in the realization that the gods of this world draw their power directly from belief—belief that can be engineered and manufactured like a commodity—and boom, you’ve got a transactional magic system that is unique, compelling, and quite rigorous. In Gladstone’s universe, the force of magic itself—the power of the gods—is actually pretty gormless and non-rigorous, but it is made rigorous by the application of Craft, and the manipulation of those rules in accepted ways. That is some deeply magical thinking.

The Cosmere novels, by Brandon Sanderson

Magic System Rating: 10 (You Got Science in My Magic)

Unsurprisingly, the man who wrote one of the most influential modern essays on the fantasy genre (and who’s also kind of successful as a writer of fantasy fiction) has produced one of the most rigorous magic systems in history. For extra points, the magic system he’s crafted, Investiture, is a stealth meta system that encompasses several other already-rigorous magic systems laid out in separate fantasy series that have slowly been revealed to be not so separate after all—to be, in fact, part of a larger, integrated universe. Sanderson’s achievement here can’t be understated: Investiture is only partially revealed at this time, but what’s clear is that the different magic systems found across Sanderson’s books—from Mistborn‘s Allomancy (the manipulation of ingested metals gives users superhuman abilities), to Warbreaker‘s BioChroma (magical power is drawn from colors present in the user’s environment), to Elantris‘ ritual-based Dor—all follow the same general guidelines, as they’re all part of the meta-system he’s crafting. It’s all quite detailed and consistent, yet tons of fun to think about.

Dungeons & Dragons

Magic System Rating: 11 (Ph.D.-Level Magic)

Okay, it’s not strictly a work of fiction, but by necessity, D&D remains the gold-standard for hard magic systems—because if it wasn’t, the game it powers wouldn’t work. Every single detail is mapped out, every aspect of magic is controlled and explained, and every outcome makes sense based on detailed rules of interaction. The real magic here is how the, um, magic of magic is maintained despite the rigor applied to it; in part this is due to the introduction of chance in the form of a roll of the die and the (typically) unknown stats of the object of your spell, but part of it also stems from the spirit of the endeavor: D&D isn’t trying to suppress your imagination or sense of awe, it’s just seeking to channel them in a coherent and replicable fashion.

What books have your favorite magic systems, and how would you rate them?