A common problem with generic role-playing systems is that they often have non-generic answers to important questions.

For instance, Traveller was originally meant as a generic SFRPG, before it started generating a setting that pretty well took over the line in later iterations. But even sticking with the early, non-setting specific materials, it still has a number of assumptions built into the basic rules. Most notably, a severely range-limited hyperspace FTL system keeps it from feeling like, say, Star Trek, without going in and completely redoing that section. Similarly, for some time GURPS had a single magic system, that while very good in its own right, had its own flavor. Other systems got introduced in various worldbooks during 3rd Edition, but it would take a 4th Edition book to really look at the problem.

GURPS Thaumatology is a big book about magic systems (plural). It has a number of different systems to use, and some general talk about the ways magic can work in a world, and how this might be reflected in the game, all so a GM can have a system that feels right.

Variations on a Theme

Thaumatology starts out with a chapter on how magic works in general (magic as art vs as engineering, Law of Contagion, etc.), and then goes on to an extensive chapter that just deals with tweaking the normal GURPS skill-based system.

Just doing that provides a lot of food for thought, with a vast array of options. This ranges from different tweaks to the advantage that allows spell-casting, to the possibility of basing spell casting on something other than intelligence (say, willpower). There’s discussion of changing around the spell lists (including one thorough worked example), and prerequisites, and even a look at what types of shapeshifting fit with different background cultures. And there’s a too-brief look at how to enforce the ‘mages wear robes’ trope (the two methods looked at are skill penalties for encumbrance or for the amount of iron worn). In all cases, the options get the usual GURPS thoughtful look over, complete with the likely effects on the game.

The chapter after that presents bigger variations on the standard system; these are sections that deal with an overall rework of the system, instead of a bunch of little options. The first one is the idea of using the skill-based system for clerical magic as was presented in GURPS Religion, with a few more notes added.

After that comes a section on Ritual Magic, which is an expansion of a system suggested in Basic Set. There, it got about half a page, and here it gets four, which goes much more in-depth as to how to make it work. In this case, it simplifies the skill system down to colleges, with all the spells in the college attached directly to that. Then comes Threshold-Limited Magic from an early issue of Pyramid, which replaces the fatigue cost with a tally that limits casting by putting the mage at personal risk when he does too much.

Then “Mandatory and Significant Modifiers”, are more of a tool kit again. It proposes giving skill modifiers for various astrological or symbolic concerns, possibly being used to overcome a flat overall penalty (or they may be needed to be able to cast at all!), and several tables in the appendix give details. Finally, “Assisting Spirits” has the idea of a character getting a large break on spellcasting… by making a contract with another being that provides the bulk of the power—at an appropriately steep price.

Physical Magic

The next chapter takes a look at the use of physical objects for magic, first looking at the inherent properties some things may have, and how they could be used as another system of modifiers for a regular spell-casting system. Then about seven pages are given to alchemy, including thoughts on allowing characters to come up with new concoctions, or even treating it as a gadgeteer advantage.

After that, there is a serous look at enchanting items, starting with the standard systems given in Basic Set and Magic, and how they can be tweaked for the needs of a campaign. Some more serious alternatives are looked at with the idea of age granting power to items (after all, all the most powerful items in fiction are immeasurably old…). Also covered are all of the possibilities of great deeds, regular use and the like causing an item to become magical on its own. Finally, there is a discussion of items with a will of their own, from how they are created under the normal enchantment rules, to how to write them up as a character.

The Path of the Book

After this Thaumatology finally starts going further afield. The next chapter covers what’s called Path/Book Magic, which is based off a Third Edition system that originally appeared in GURPS Voodoo. Meant to act like a lot of real-world magic traditions, all ‘spellcasting’ is in the form of rituals that generally involve gathering energy, and then expending it for the particular effect. This is still effectively a skill-based system, but it concentrates on one skill: Ritual Magic. That skill, and skills for each particular tradition—a ‘path’ or ‘book’—makes up all the skill entries on the character sheet, which is a lot more compact than the normal system.

However, each tradition contains a limited number of particular spells, which are then cast at a specified penalty to the base skills. These are also more general spells than the standard ones, with the area of effect, duration, or number of targets being decided by the caster, which modifies the skill, energy, and time needed. The system is arranged around wider-ranging, and more subtle, effects than the usual ‘mage as artillery’ systems seen in many RPGs, though very high skill levels can allow a character to shortcut many limitations. After a fairly thorough grounding in the system, the chapter concludes with ten sample paths and three books.

How to be Flexible

The next chapter then gets to the idea of cutting loose from pre-defined spells completely, and gives a couple major versions of that idea. The first is the use of symbols, or runes, which give a set of concepts to work with, which are then combined into a spell. This allows for inventiveness from the player, and the use of Symbol Drawing skill and skill in each symbol used (which means a character can easily be better at certain types of effects). Thaumatology then gives a couple of sample traditional systems, and gives ideas for using rune stones or drawing symbols fresh and the like.

Then is Syntactic Magic, which works similarly, with everything split up into categories, which need to be worked out by the GM, though two general schemes are presented: First, ‘Verb-Noun’ magic, where every spell consists of what is being done to whom. It’s mentioned that mages can potentially leave some normal parameters (like duration) undefined, and let his margin of success determine it. To that end, there’s also options as to whether certain effects take more energy or more skill to pull off, and lots of advice and tables for modifiers, depending on which way the GM goes. Second, ‘Realms and Power’ focuses on how much a mage can do with any particular realm as defined by leveled advantages (one side box also discusses the possibility of recasting this entire idea as a power structure from GURPS Powers, which would be mechanically much more complex to work out, but would tighten up the mechanics and definitions—which is great for consistency, and horrible for letting the GM insert plot-appropriate easing and tightening of restrictions). In both cases, the emphasis is on flexibility, with characters/players defining what they’re doing as they go, with the system defining what the limits and costs are, instead of working with a rigid list of spells.

Magical Advantage

The last ‘crunchy’ chapter points out that many of the advantages presented in Basic Set could easily have a magical origin. There’s some good discussion of how some traditional magical powers are represented in advantages, and there’s a couple pages of recapitulation of the basics from Powers (which is good for not requiring that book for this, but is the type of repetition that 4th Ed has tried to avoid). There’s good advice on supernatural servants (bound demons, spirit familiars, etc., done as Allies and Patrons), and spirit vessels (someone possessed by a spirit), effectively the methods where a character gets magic from another character.

My Kingdom For a Mage!

At the end of the book, Thaumatology returns to the discussion of magic instead of magic systems it began with. In this case, the chapter is about the nature of a campaign dealing with magic, and magic’s place in society and the like, instead of general thoughts of how magic works. One of the first sections notes that it probably not worth the GM’s time to work on an elaborate magic system unless magic is going to be a central pillar of the campaign. …It would have been best to present that advice up front, before going through two hundred pages of just that.

The more social discussion is then followed up by thoughts on particular game styles, most clearly when it comes to emulating how magic seems to function in a lot of superhero stories. The chapter then finishes up with four different campaign frameworks, describing settings where the nature of magic has much to offer in terms of adventure.


One of the brilliant moments of GURPS Space was boiling every form of FTL travel down to one of three general types and then showing how to vary them to produce anything ever seen in science fiction. Of course, how FTL drives work doesn’t really have any real influence on game mechanics the way the intensely personal nature of spellcasting does. Still, I consider it a missed opportunity that Thaumatology, for all of its wide-ranging discussion of a number of different systems and their variations, doesn’t even begin to provide a framework of discussion by taking a real comparative look at its own systems, grouping and giving an overview of them.

It is also worth noting that there are four different magic systems that currently get a fair amount of use in GURPS, each with its own distinct mode of operation, and none of them are in Thaumatology. The original magic system (magic as skills) presented in Basic Set and Magic still gets most of the attention. Second is Ritual Path Magic (magic as player/GM mediation) which got its own supplement after being introduced in Monster Hunters, but drew inspiration from several parts of Thaumatology. Divine Favor (magic as Patron) isn’t nearly as popular as the first two, but does see regular use. Finally, Sorcery (magic as Powers) just recently came out, and perhaps won’t see that much use, but so far seems to have a lot of people wanting to use it, and is based off a popular idea.

In the end, Thaumatology is an expansive, wide-ranging book with a lot of ideas for the inventive GM. But, while it has several pre-packaged systems, if that’s what you want, you’re better off skipping this book, and going for one of the ones mentioned in the previous paragraph. If you don’t play GURPS, but want to tinker around with a different magic system, this isn’t as good at cross-system inspiration as some other GURPS supplements, but it does have a lot to say, and there’s very little out there that addresses the the question at all.