The Black Emperor; zeref

Zeref Dragneel (ゼレフ・ドラグニル Zerefu Doraguniru) is considered to be the strongest, most evil Mage of all time, who possesses extremely dangerous, and powerful Magic. He is the founder and current Emperor of the Alvarez Empire, under the alias of Emperor Spriggan (皇帝スプリガン Kōtei Supurigan), the older brother of Natsu Dragneel and the father to Larcade Dragneel.