War has come to Equestria. Annoyed by the idea of equality, King Dain of the caribou tribes invades Canterlot to bring its citizens to heel, while in the northern mountains the minotaurs attack Griffonstone; The capitol of the griffon kingdom and deep below the earth the changelings fight a desperate battle against the savage diamond dogs. To combat this evil, Equestrians, Griffons and Changelings have cast aside their differences to form a grand alliance for if they fail the forces of darkness will conquer all.