So, Advanced Fighting Fantasy just happens to include four(!) different magic systems. Now, to be honest, two of them – Minor Magic & Wizardry – are essentially the same “system” (roll to cast, burn Magic Points) just with different spells (MM spells are much lower in power). Sorcery is mechanically very similar to MM and Wizardry (roll to cast), but has some flavor differences and, most importantly, is powered by burning actual Stamina (i.e., Hit Point) rather than the substantially less painful expenditure of Magic Points associated with Minor Magic & Wizardry. And then there’s the Priestly approach to magic, which has some mechanical differences (no rolls to cast being the biggest, no MP or Stamina costs being the other) and limits its practitioners to many fewer spells/effect. So these systems aren’t as wildly divergent as, say, BRP’s Magic and Sorcery as presented in the Big Gold Book. But still, the differences are there.
What’s awesome here is that the functional differences between Minor Magic/Wizardry and Sorcery makes for a delightful opportunity to take the game in either a high fantasy or swords & sorcery direction just by which system(s) you choose to use. Minor Magic and Wizardry – either alone or used in conjunction – speak to high fantasy (though MM by itself might be only half high fantasy). Meanwhile, Sorcery, with its high personal cost of burning Stamina to cast, is (no surprise, given its name) perfect for a swords & sorcery feel. If you decide to use all four systems, you’re clearly in over-the-top fantasy land, which can certainly be a fun place to visit. Oh, and I suppose if you went with just Priestly magic, you’d be in a very interesting place as well. I’m not sure what you’d call that place, but it might make for an interesting Ancient World kind of feel, where only the devout were throwing magic around.
So not only is AFF a delightfully simple system to play with, it manages to be highly configurable. Mix & match magic systems to taste and you’re off and running into the fantasy feel you want to explore.