30 wounds (+1 if you count the lore attribute) from a single spell. Granted, it was the 18" range one, but still...that's quite a lot. I think the key is to use high-level wizards. That way you get a minimum of 4 or 5 wounds per unit.
In any case, rolling for CoY on the Black Widderz. The character is on the left, followed by the unit champion, then all of the other guys. Needing 6+ to wound...