A month has passed since Tirek's defeat for Twilight and the Elements of Harmony, but one call changes everything. An invitation made by Lord of the Underworld, king over Tartarus (and last of the Balrogs). Will he be a friend or an enemy of Equestria?
(Displaced without the multiverse stuff, the character does not faithfully represent the LOTR lore, only the MLP chronology will be maintained)