Zeref Dragneel

Zeref is the most evil wizrd in the Fairy Tail universe. He is known to be still alive and sealed in a multiple lock prison. He is trying to be set free by using his loyal followers who are now the Dark Guilds.

Backround
Zeref is known to be from ancient times and that in his present state, he can only be seen by people with a lot of hatred at the moment. At one point, he used a young Jeral to help him get rid of one of his prisons keys. In the long run he was succesful in his plot.

At the moment, Zeref is using the Ballard Alliance to help find the keys to his prison. Ultear seems to be his most loyal follower.