I wonder, with the Sargeras storyline, seems likely that there could be a race of demons creatures in the twisted nether even stronger than Sargeras himself.
But is that really possible? could we eventually come into conflict with a new more powerful race of demons, after we defeat Sargeras again in a later X-pac?
Sargeras is the most powerful being in the legion right? So could there be Demons outside the legion that are more powerful, or does the legion control all demons?