They did a lot of cool things with the way the environmental effects interact with each other. All the rain, smoke, poisonous gas, tornadoes, explosions, lightning chaining through blood and water alike, etc.; all of it is really awesome. They've in this game done environmental effects in-combat better than any other game I've played.
But sadly, the spells themselves are really boring and uninspired for the most part. The early-midgame ones are functional and do what you expect spells of that level to do, but the end-game ones are pretty lame, if they're worth casting at all considering their AP costs and frequent unreliability.
