Updated through 1210
Durkon Allotrope Thundershield, Kraagor (as statue), Minrah Elle Shaleshoe (as Large size), Redcloak
I'm considering adding "imploded" as a "notable alteration," both for Durkon and for the elves that Redcloak imploded way back in Book 5. I'm not sure whether it counts as an "alternate magical form," though - it certainly seems on par with being charmed, which counts, and it's certainly a magical alteration, but is it really an "alternate form"? Thoughts?
Also, Minrah has now appeared in as many strips as Thog. By that metric, she's now tied as the 19th-most-significant character!