Instead of defeating the villain trio by combining the power of friendship yet again, Twilight and the others lose in their desperate attempt of victory to save Equestria.
Equestria faces its most dire threat yet as Grogar and his legions march upon Canterlot. Meanwhile, Cozy Glow, Chrysalis, and Tirek prepare to betray him and seize power themselves. Can the Mane 6 save Equestria?