Source

When dark creatures begin appearing in Equestria, Princess Celestia and Princess Luna summon the bearers of the Elements of Harmony to Canterlot. Before the six ponies can arrive, though, four strange ponies are expelled from a portal that appears in the throne room, and they explain that Equestria is not the only place at risk from these creatures. Thus begins an adventure that will reveal a greater destiny for Ponyville's librarian than she could have ever dreamed of.

Kingdom Hearts/My Little Pony: Friendship is Magic crossover. Pairings undisclosed.

It's lunchtime in Ponyville, and Twilight Sparkle's stomach is calling for something with a little more flavour than what she usually feeds it. How will she and her friends react, though, when the lavender unicorn discovers that there is no place in Ponyville where a pony can get a decent burrito?