For all their power, the Elements of Harmony are bound by one common rule:
They cannot kill, no matter how dark, how unnatural the force is.
They may purify, they may banish, and they may petrify, but they cannot kill, and redemption is not always a guarantee. Fortunately, their power was enough to save Princess Luna from the nightmare that possessed her, body and soul. She was freed from its icy grasp. She was purified.
Yet the nightmare still lives...
Thank you to Sable Tails, who has graciously helped as an editor and someone to provide early feedback.