Mard Geer Tartaros

Mard Geer Tartaros (マルド・ギール・タルタロス Marudo Gīru Tarutarosu) is the main antagonist of the Tartaros arc in the manga/anime, Fairy Tail. He was an Etherious and founder of the Dark Guild Tartaros. He was known as the Underworld King (冥王 Meiō) and the Definitive Demon (絶対の悪魔, Zettai no Akuma), having placed himself in charge of the guild in E.N.D.'s absence.

He is voiced by Toshiyuki Morikawa in the Japanese version of the anime, and Vic Mignogna in the English version, the former of whom also voices Naraku, Yoshikage Kira and Griffith.