This story is a sequel to Decretum

Almost a decade after his parents vanished in the war with Clockwork World, Antares Mirus is finally ready to try and find his parents, to save them as they saved him. But his plans are interrupted when a psychotic force of destruction rises out of dormancy, targeting first Ponyville... and then the unfortunate Antares himself. Seventh story in the Blooming Moon Chronicles/99 Worlds Saga.

Before he can set out on his journey to save his parents, Antares Mirus gathers his friends and tells them the story of his parents, from when Luna was Princess of the Night to when she and Scrivener Blooms vanished during the war with Clockwork World. Sums up the entirety of the Nátta Edda, prequel to Absolution.