"Now Nightmare Moon is free again and has spread the night throughout Ponyville..."
Nightmare Moon will mock you as you try to drive back the darkness and restore the Harmony Stones.
Defeating Nightmare MoonEdit
To defeat Nightmare Moon, you at least must activate all six Harmony Stones and have the following residents in Ponyville: Twilight Sparkle, Pinkie Pie, Applejack, Fluttershy, Rarity, and Rainbow Dash.
After defeating Nightmare Moon, Princess Luna is added to your inventory.