Fan Fic / Upon A Falling Feather

A My Little Pony: Friendship Is Magic fan fiction by ezra09. It is an Alternate Universe Fic that takes place in an Equestria where Air Ships were invented, and Sky Pirates are everywhere.

After losing her family fortune, Rarity, along with her best friend Pinkie Pie, turns to piracy to make ends meet. The two of them commandeer a magical airship and kidnap the princess's personal student.

When Princess Celestia learns of Twilight and Applejack's abduction, she doesn't agree to pay the ransom. Instead, she hires the sky's greatest tactical mind, the Daring Swordspony Rainbow Dash, and her sidekick, Fluttershy. Together with Shining Armor, they track down Rarity's ship in order to save Twilight. As the two groups engage in a game of cat and mouse, more dangerous threats slowly bubble to the surface. Aztec Curses, angry gods, and a mysterious figure known only as the Derp Pirate Roberts.

Can be read over here.

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