This spell is not bad.
With max buff extension AA,it will last for 9 mins.
DMG/Mana ratio = 62208/2364 = 26.31 which is way better than other nuke(if not compare with focused/AAed/buffed nuke).
Something strange tho.Lucy shows it has hit limit for 48 hits,but I only parsed a merely 36 hits.
Maybe they already changed it./shrug