Miasma II on single target was 200 potency if allowed to tick fully, that's how people used it and Energy Drain together in Savage because of Quickened Aetherflow optimization. Ruin II is all of that upfront, making it more DPS for less micromanagement. On AoE it was 120ish per target if spammed, higher if not. Art of War needs to spammed to exceed it, but if you only cast a healing spell every 5 GCDs they're about equal.