The Day of Long Death refers to the final day of the Black Clan War. On this day, Orin Aramar enacted his long-suffered plan to overthrow the delusional despot, Satō Seiza. In the very city in which the Betrayer's campaign had started, the final stand of the Atsuko army took place.
With several caches of hidden weapons and technology, the citizens of Ninava responded to Orin's signal and began to take back their country. The rebel armies of the Aramar as well as the armies of the Daisuke joined forces to end the reign of the mad man that had stolen their nation from them. and succeeded.