Champions of the Lich King
Years after the destruction of Draenor, the immensely powerful Lich King created a new breed of death knights: malevolent, rune-wielding warriors of the Scourge. The first and greatest of these was the Lich King's chosen champion, Prince Arthas Menethil, once a mighty paladin of the Silver Hand, who sacrificed his soul to claim the runeblade Frostmourne in a desperate bid to save his people.
Unlike Gul'dan's death knights, these dark champions do not possess free will and their minds are inexorably entwined with and dominated by the Lich King's vast consciousness. Despite the heavy costs of free will, some powerful mortals are intrigued by the promise of immortality and pledge their souls freely into the Lich King's service to achieve it. (Baron Rivendare is an example of this).
In the years since Arthas shattered the Frozen Throne and merged with the Lich King, the power and fury of the death knights has only grown. Now these unrelenting crusaders of the damned eagerly await the Lich King's command to unleash their fury on Azeroth once again.
The Ebon Blade
The Knights of the Ebon Blade is a faction consisting of the renegade death knights that broke free of the Lich King's control after the battle of Light's Hope Chapel (in other words, player-created death knights). Led by Highlord Darion Mograine, the Knights of the Ebon Blade have allied themselves with the Alliance and the Horde with the help of Highlord Tirion Fordring of the Knights of the Silver Hand, and have pledged to do their part in defeating their former master, the Lich King. Their main base is Acherus: The Ebon Hold, a former scourge necropolis in the Eastern Plaguelands.)
