Fifteen years have past since Soarin' and the Equestrian Army prevented the splitting of Gryphus, the griffin kingdom, from collapsing at the hands of an uprising orchestrated by an organization known as "Lumisade."

Fifteen years later, Soarin' receives a letter from an unknown griffin who goes by the name of "Ribbon." In the letter, Ribbon claims to personally know some of the griffins Soarin' and his team fought against. Ribbon wishes to know the final moments of his guardians, Fritz "Himmel" Granz and Hilde "Engel" Rosenkranz. Filled with regret, Soarin' chooses to write a detailed account of his part in "The War of Wings" and the final moments of Ribbon's parents.

Their letters present two different paths that lead to the same end: the death of Ribbon's guardians and the end of the war. Through Soarin's jarred recollection, the members of Lumisade appear as griffins with the sole purpose of destroying Gryphus to spread their misguided ideals of nationalism and how their near-fatal skirmishes in the sky marred his psyche. From Ribbon's childhood experience with Engel and Himmel, Lumisade is represented through two skyfighters and their desperate attempt to survive while they willingly stand by Lumisade and fight a hopeless war against an enemy they cannot defeat.