When the Shadowbolts carried out their first campaign against Equestria, Princess Celestia created a top-secret weapons project called the Soldier With Evolving Emotions Thoughts Intelligence and Exterior Project, or the S.W.E.E.T.I.E. Project. From this project came a bio-mechanical unicorn filly known as Unit 83113. But, the Shadowbolts invaded the lab intending to claim this tech for themselves. The robot managed to find safety with the Belle family, who raised the machine as their second daughter. Fourteen years later, the Shadowbolts return, and Sweetie Belle must at last show the world what she's made of.

Co-written with VampDash.
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