Originally Posted by
Caerule
Where was this confirmed? Because people keep stating this, folks like Bellular, but as far as I can tell, but this is just speculation?
Don't get me wrong, Denathrius is a Dreadlord. And they do work with him. The Naaru was captured and delivered to Denathrius by the "unseen ones" and delivered to Denathrius. Dreadlords being present at Sinfall is double-confirmed. Denathrius being a dreadlord also explains why he didn't kill his Prince at the end of the Revendreth campain. Dreadlords have rules against killing each other, as seen way back in Warcraft 3. Denathrius can't kill those he considers kin.
But while he is the Sire that sired the Venthyr, there's no strong evidence that he was the first Dreadlord that created the others. I see it way more likely that he's just another Natherzim, that managed to infiltrate the pantheon of Eternal ones, and poison them from within, as Dreadlords do.
The Dreadlords are mighty and numerous. If he was their true master, I don't see why we didn't see any of them in his defense in 9.0.