Over a millennia ago, before the defeat of Nightmare Moon, there was an ancient order of people who called themselves Dark Signers. Nine, in particular, were called the Order of shadows, as they were not only the first but the most powerful of the dark signers. But, in the end, they were mostly defeated by the legendary signers.

Only their leader, the Shadow King, survived but went into hiding by the equestrian legendary signers after his defeat at their hands. But now, after millennia of hiding, the Shadow King, with the mark of the Hevon, and his EarthBound Immortal, Huacachina Kon, and three others, Adagio Dazzle, Aria Blaze, and Sonata Dusk. (with the marks of the LLama, Hand, and Fan), and their EarthBound Immortals, Llamaca Pacuilla, Ukupacha Callao, and Itzpzpalo, have returned with their mission to bring Xolotl, the Lord of the Immortals, back from the netherworld to consume the world in shadows.