Lore drop (outside game, he references it) the only 12th level spell ever cast was by a netherese mage who wanted to take over the body of a god to win a war. He chose the goddess of magic. The read is here,
https://forgottenrealms.fandom.com/wiki/Karsus%27s_Folly. Gale mentioned it and the thing in his body is a fragment of the distorted power of that moment. What I am hoping is that he becomes a ruthlessly powerful mage as he actually was in a relationship with the goddess of magic and wishes to regain her favor. If he explodes, he said it could wipe out a city as large as Waterdeep. Compelling story reason. Mechanically, you're right. There is also the hood from the Myconids, but its pretty awesome. I don't know exactly what, but having alternate sources that might piss off clerics could be nice. Suck the power out of shrines, things like that.
