Did you ever hear the Tragedy of Lord Karsus the Archwizard?
I thought not. It’s not a story the Clerics would tell you. It’s an Arcanist legend.
Karsus was a Lord of Netheril, so powerful and so wise he could use the Weave to control the gods… He had such a knowledge of the arcane arts that he could even keep the ones he cared about from dying. The necromantic side of the Weave is a pathway to many abilities some consider to be unnatural. He became so powerful… the only thing he was afraid of was losing his war-ravaged homeland, which eventually, of course, he did. He created the first and only twelfth level spell. Unfortunately, when he cast it he made the only possible wrong choice and supplanted the goddess of magic, temporarily ending all magic in the world and causing his homeland to fall from the sky. It’s ironic, he destroyed his entire civilization in his attempt to save it.