What are the Black Dragon Armies in World of Warcraft

In all actuality there is really only one true black dragon, Deathwing. all others that are "Black" are really chromatic, ebon, and mixbreeds with the other dragon races. Deathwing killed his own to become the most powerful of the Aspects. Maybe soon Deathwing will show what he's been cooking up in the Maelstrom.