This game is indeed fun, but my previous opinion of "bug free single player" has been revised to:
"Occasional Crashes to Desktop, particularly in Boss Fights, requiring you to do the entire level over again."
Particularly vs the Orc General, and the Chapter Six boss fight sequence.
I hesitate to even try multi at this point, as I hear it is a horror show. Still, one of the best magic systems in a game to date. Although a Permanent Shield/Permanent Haste setting would be REAL nice, having to recast so often is annoying.
*EDIT*
Hrm, workaround for the Chapter 6 crash:
Steam Forum Link