Zeref

Black Arts (黒い芸術 Kuroi Geijutsu)

He was able to master all forms of Dark Magic at a very early age, and brought countless demons to life. His Magical strength is so enormous, in fact, that he cannot consciously control his own Magic, though whether this was always the case is unknown. Zeref's lack of control over his black arts seems to come from his emotional state. He has stated himself that his kind 심장 that cares about lives causes his powers to run out of control and randomly kill, but when he hardens his 심장 and becomes the cold, ruthless Zeref of legend, he has complete control...