One of my attempts, it might be from older version, but the strategy is still viable and working - put challice (or any healing) in the first slot with 4/4 spihon, and upgrade it each 10 levels just to outscale enemy damage - 10% of this healing will put You in unkillable state. Then, put other weapons in every other slot, any weapon that strikes 2 times per turn (blood fang and frost gem have the best value), and dismantle blood blade onto them - doesn't matter what quality. Then, enjoy winning every fight with turbo dmg scaling :) 