Other than the King of Dead Onyx, who held absolute authority as the King of Death. Under his command were one Prime Minister of Dead, two Dead Ministers, and four Dead Dukes, followed by Dead Marquises, Dead Counts, Dead Viscounts, and Dead Barons. These were the highest ranks of dark beings, and they all controlled their own fief and races.
The Dark Beings followed a strict hierarchy, the high-evolution dark being had an absolute advantage over lower-evolution dark beings, and all those Dead Noble Titles were earned after going through countless bloody battles and getting Onyx recognition.
The Prime Minister of Dead, and two Dead Ministers lived in the Doom Palace in the Doom Capital, and only the King of Dead can command them.
But the four Dead Dukes handle the East, West, South, and North of the Dead Plains, and they only had one purpose, kill as many livings as possible and train powerful Dark Knights for the Doom Capital.