Harmony rules Equestria. Twilight Sparkle is the new princess of Canterlot. Discord has been reformed and Queen Chrysalis hasn't be aground for a while… but it is soon revealed that an ancient primordial evil of Equestria that was believed to be vanquished millennias ago is on brink of returning.

Twilight is going to need all the help she can get from her friends to combat against Anger, Hatred, Doubt, Despair, Fear and maybe against even one's own…Pride.