Once again, poor Princess Luna misses out on the adventure. While Twilight Sparkle and her friends were saving the Cutie Mark Crusaders and Princess Celestia and Spike defended Canterlot, Princess Luna was nowhere to be found. Just like the Royal Wedding.
But that doesn't mean the beloved Princess of the Night was taking it easy during the passing of the Secretariat Comet. Canterlot was not the only city that was threatened by magical beasts enhanced by the comet's strange magic, and Princess Celestia wasn't the only Princess defending her subjects that night.
Only...something is different with this monster that is attacking Manehattan. It is unlike anything Luna has ever seen, and when even her enhanced magic from the comet fails to stop the creature, she must find another way to defeat it before it destroys her and the city.