ToME: the Tales of Maj'Eyal

see title; hiemal shield is a sustain, and is not temporarily until after you de-sustain it, and so, shattering blow shouldn't pop it
however, I managed to pop it vs. 2 necromancers, so this presumably isn't working as intended

This makes me wonder if it can remove Disruption Shield as well. I haven't tested it, but it's another sustain that gives a shield.