I'm a fire main and I tackled easy Strong Approaching with a lightning main team. We had probably the best healing/debuff clearing/interrupting/combo team that our ninja allow, and we beat the instance maybe 3/4 times once we got a rhythm going. Before that, though... it was frustrating because Shizune's heal would basically reset the instance and the poison would wear us away, but we both had Kabuto and Sakura so we'd be back to near-100 by the next time she healed, so we basically made no progress at all. Hanzo actually wasn't difficult if you could interrupt the first and third mysteries, which I did.