Allow me to suggest the fine FUDGE supplement, "A Magical Medley", by
Grey Ghost Games. It includes systems for African Spirit Magic, Celtic
Magic, Chinese Magic, pseudo-scientific Gramarye (for a mythic medieval
campaign), and assorted others. Highly recommended and very easily
adapted to other game systems.
Specifically useful to Gloranthaphiles are the African Spirit Magic
(shamanism), Chinese Magic (eastern magic), and Gramarye (sorcery).
Celtic Magic, with some tweaking, could be used as a core for the theist
approach, although the manner of general magical abilities would need to
be broadened.
Michael Schwartz mschwartz_at_mindspring.com Ann Arbor, MI USA
"I've always said you can get more with a kind word and a two-by-four
than with a kind word alone." -- Marcus Cole, Babylon 5