My favorites of all time

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  My Two Most Faithful Students Twilight changes Star Swirl's time spell to travel back to the past once more. She ends up in the Pre-Equestrian era and unwittingly saves two fillies in the process. Little did she know what teaching them magic can do for the fate of Equestria. by Flaeirye 44,179 words · 2,002 · 33
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  Help! I'm not a changeling! Well, this is new. A new body, a new life, a new beginning. It would be great if I didn't have to realize that this new beginning is going to be the end of me. Oh boy. by Ashardu 92,370 words · 604 · 58
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  Princess Celestia Gets Mugged Princess Celestia disguises herself as a younger mare and goes for a walk around Canterlot where she promptly gets mugged. Now on EqD. by BronyWriter 17,343 words · 5,424 · 71