Warlord with Mystera is so strong that I did a parched Gnome run in the end - even though Gnome is a top-tier Warlord-Mystera synergy. It only takes a level-up from 7 to 8 to do this boss, though, or maybe it was 8 to 9. Anyway, no damage items, but Mystera was plenty.
Corrosion is actually more fun on a Warlord than I thought. At least, at early levels you can reach some big kills that would otherwise be just out of reach. Fine Sword probably could've done the same faster, seeing as I only needed a few stacks.