Artist: Karl Waller
Source: Complete Book of Necromancers (1995)
Spell: ...Mage Armor? Maybe Spirit Armor from ToM?
...I dunno, just one that's imprinted on my brain. I loved the Complete Book of Necromancers for essentially being a stealth mini campaign setting, and having all the art of spells in the book be of them being cast by statted NPCs that appeared toward the back of the book - Kazerabet, in this case.