The battle itself was relatively short. The Knights of the Ebon Blade were led by Highlord Darion Mograine, in an attempt to claim the hold. Arthas had been defeated in the earlier Battle for Light's Hope Chapel, and left a severely weakened Patchwerk in charge of an unremarkable force of Undead Scourge. The Lich King greatly underestimated the Ebon Blade's forces, as Patchwerk was defeated and the knights claimed the stronghold.
Patchwerk survived the encounter, returning to Naxxramas as Kel'Thuzad's avatar of war. The Lich King lost much that day, as not only did many of his strongest recruits leave him, but his important strategic base Acherus was claimed by his enemies. The Knights of the Ebon Blade still use Acherus as their capital to this day. Inside, masters train young Death Knights battle and magic. The Knights have joined forces with both the Horde and Alliance in the aftermath, uniting with the enemies of their former master.