What Makes a Great Magic System?

[Michael Cule]

There's something to be said for having magic use the same type of mechanics as the rest of the game but there's also something to be said for not having the same set of mechanics for different types of magic. If your mage/sorcerer/wizard is using skill based magic that he powers himself then maybe your summoner/shaman is negotiating with spirits to get them to do stuff and the priest of the gods is following a path of piety and ritual and doing something entirely different.