Talk:Sunset Shimmer/@comment-24208499-20131207110722/@comment-4589864-20140120223111

Uh,  that's not at all how Sunset found the mirror. Princess Celestia showed it to her in The Fall of Sunset Shimmer when she was Celestia's student, and then Sunset studied it in a book behind Celestia's back when the princess refused to tell her any more about it. There's no mention at all of Starswirl, Fort Canterlot, or those three stars being factors in the portal's usage or activation.

If that's fanon, then put that aside. In my fanfiction, Sunset Eclipsed, the portal also opens for one-way trips between the worlds every thirty nights. That way, one could travel from one side to the other if they were to find themselves stuck in the wrong world.