Princess Luna disappears from Equestria with hopes of saving the world and is accompanied by the enigmatic Sombra. Meanwhile, Celestia tries to bury secrets as immortal as she is and Cadance must choose her loyalties carefully...
Aria will protect her cousin from anything, even if she is a burden, especially when it comes to the newcomer to their duo, a siren filly named Adagio Dazzle with plans of her own. [Siren Origin Story]