Twilight, the one pony from the lunar colony to ever graduate from the Divine Princess's School, sees that the colony's spell nexus is alive... and it calls itself "Luna"... and it wants her to lead a revolution. Thematic-only crossover.
It's been eighty-nine days since the Day of Darkness, and Twilight Sparkle is still on her own. Eighty-nine days since she talked to anyone other than herself.