You might want to stop at the Bazaar and buy a cheap Myth wand.
Use Storm Prisms in this battle. Put one each on Katenstein and the Potbelly, use a Stormblade, and cast Tempest at 5 pips or higher. That will get rid of the minion. Then repeat with the prism on the good doctor, blade, trap, and Kraken. If a myth shield exists, knock it off with the Myth wand spell.