It is a century after the war of the two cities, a time when the line between pony and machine is becoming blurred. And yet, even now when ponies are connected in so many ways, something wants to disrupt the fragile network of society.
It was a grimoire. Not just some podunk D&D spellbook, but a limited-edition "Grimoire of Marisa." How could I pass that up? Turns out, very easily. Well, at least I didn't cosplay as one of the actual characters; I don't have the legs for a dress.
Schadenfreude is a butler to Blueblood and he's no stranger to being tossed in the dungeon for ticking him off. He decides to tell the story of how he got there this time.
Upon her return and when confronted by the new Bearers of the Elements of Harmony, Nightmare Moon decides to summon the foulest creature to ever exist (at least she thinks so).
Each time Twilight tries to stop Starlight, she fails and is flung to a new, twisted Equestria, each one worse than the one before, until she lands in one that isn't worse. The only real difference is that her castle isn't there. But the library is.
Celestia was a filly living on an isolated farm and harboring dreams of greatness. Chrysalis was a black goo poured out from a wound in the walls of reality and with a weak grasp on the amount of fangs one should have. Friendship happened.
The princesses gave their magic to Twilight to prevent Tirek from stealing it. As a result, they end up stuck in Tartarus. The fact that things manage to go downhill here says a lot about the wonders of family.
A much older, arguably wiser, somewhat darker and definitely crazier Twilight Sparkle switches minds with her younger self to FIX EVERYTHING that went wrong before
In the future, we'll colonize the solar system, cure cancer, clone the human genome, and build trans-dimensional hoodies that can summon tiny talking horses from an alternate universe. It's pretty snazzy.