Sathonyx, also known as "Baron Sathonyx," the "Helfather" and as the "Lord of the Middle Dark," is the Drukhari Lord Hellion, the master of all the Hellions in Commorragh who essentially serves as the de facto overlord of the Dark City's criminal underworld. His title of "baron" is of his own invention.
In the rotten underbelly of Commorragh there dwells a warrior who commands the dispossessed, ruling over an army of outcasts like a cruel king. It is whispered that not a single Hellion gang rides to war without his blessing, and that only each gang's leaders know how to find his airborne court, for the Baron wears secrecy like a tattered shroud.
Sathonyx was once a Drukhari noble of some standing in the Kabal of the Slashed Eye, and his boundless thirst for the thrill of realspace raids was well known. It was during the Alaitoc Raids that Sathonyx captured no less a prize than an enemy Farseer, a fact proclaimed loudly to all who would listen upon his return.
As far as Archon Cythrax, lord of the Slashed Eye, was concerned, however, Sathonyx has placed the entire Kabal in jeopardy by bringing a psyker into his house. Sathonyx was banished and escorted into the bowels of the Dark City by his own Kabal-brothers, Seeing with rage, Sathonyx waited for his moment, killed his guards in an wrathful frenzy and fled into the undercity.
From that day forth there has been a high price upon Sathonyx's head. Experienced bounty hunters and alien bloodhounds took up the chase, but one by one they were found strung upside-down from the towers and minarets of the Slashed Eye.
Next came the elite Kabalite Trueborn, who carved a red path through the guts of the Dark City in order to bring Sathonyx before Cythrax's throne. Somehow he evaded even them.
Sathonyx slowly earnt himself serious respect as a survivor who fought tooth and nail every day of his life. As his legend grew among those who resented the stranglehold of the Kabals, the "baron" gathered a ragged army of exiles, rebels and iconoclasts. In a year-long campaign of fire, he brought the house of Cythrax to its knees.
To this day, not even his most senior lieutenants know of the baron's secret. Amongst the trinkets that line his bloodstained coat are the remains of the very Farseer whose capture led to his banishment.
By scattering these crystal-veined bones in a pool of blood, Sathonyx can see dimly into the future. Because of this the baron is the bane of his hunters, and his court of sky-borne exiles always remains one step ahead of their pursuers.
Baron Sathonyx enjoys a grudging respect from the archons of the upper spires. Better the devil you know, they say; since Sathonyx's ascendancy the Hellion gangs can at least be bargained with, for they have no loyalty save their allegiance to the Lord Hellion.
What those same archons would never admit is that the baron is an expert at espionage and blackmail; the fact that some of the more recent rulers to seize power once belonged to Sathonyx's Hellion gangs is a closely guarded secret.
The baron sees all, as Sathonyx like to say. Given that he has risen from disgrace to become the kingpin of the Commorrite underworld, perhaps he is right.
- Codex: Dark Eldar (5th Edition), pg. 48