Instead of The first movie having an ending where Sunset is defeated quickly; when Sunset turns into a demon, makes Snips & Snails demons and mind-controls the students and then when deciding to return to Equestria, she has another plan in mind: Instead of throwing the fireball that would insure quick defeat, she goes back into the mirror that leads to Equestria to have her former mentor Celestia ‘dealt with’ instead with her demonic duo, Snips & Snails and the mind-controlled students of Canterlot High following behind as they attack Twilight and the human five just buy her some time. With Twilight and Spike racing after her to save her friends before Sunset gets her revenge on her former mentor, Celestia.