[Death Ray] was one of Raging Flames Monarch, Nephis', most proficient skill.
Logically, once a BOSS reached the level that Nephis was in, any casual wave of the hand would be equivalent to a wide-range AOE magic skill. As a monomer skill, [Death Ray] wasn't one of Nephis' most prominent skills.
Even though this was a monomer skill, its characteristics were extremely evident. Not only was its damage extraordinarily high, it was also an instant skill with incredible speed.
It was merely a blink of an eye from the time Nephis raised her hand to the moment God of Death's Right Hand died. The others didn't even have time to react which showed just how quick the skill was.