The land of Equestria has been flooded, and the two princesses that watched over the land have mysteriously vanished. Without leadership to control the masses, pony-kind had faced years of panic. Today, some have managed to build a sustainable community amongst their land. However, others have resorted to greed, deceit and piracy to be the foundation for their new way of life.

Ponies of the land and air have once again segregated themselves from each other, but a trio of fillies has kept their friendship intact. Using their desire for adventure to bring Equestria back to the way it used to be. The only way to do that, is to put their faith in a legend that may lead them to a fabled city under the sea, journey across the perilous ocean, and face a number of blood-thirsty pirates bent on discovering it for themselves.