Death Lord

It is name of one of the Masters of the Darkness and Lord level Class that is higher than the Necromancer that Muyoung was after.

To obtain this class you have to complete the trial for unique class necromancer in certain amount of time and impress the Masters of Darkness.

Undead created by Death Lord weren’t simply different in appearance, but they were far stronger than a typical undead. They even had an amazing ability to think for themselves and had cognitive capabilities. They are also able to evolve by devouring each other.(According to level of Art of Death)