Gurps Chaos Magic

[johndallman]

Originally Posted by FuddFenderson

Good sir I mean exactly the postmodern definition.

Aha! GURPS does not have a ready-built system for that, but it does have good tools for building custom magic systems. Start with GURPS Thaumatology, available here.

Authentic Thaumaturgy, available here, is not a GURPS book, but it may well help with the problem of making rules and setting limits for chaos magick. That isn't really in the spirit of that art, but is necessary for a game.

You may be able to save yourself work by "re-skinning" one of the many existing magic systems, such as Thaumatology: Sorcery or Thaumatology: Ritual Path Magic. However, you're going to need to refine your model of chaos magick before you do that.

Addendum: Realm Magic, which is in Thaumatology, was suggested above. Another candidate would be Path/Book Magic, most of whose effects can be interpreted as lucky accidents or coincidences, which is appropriate for real-world systems that actually work. That's also in Thaumatology.