The Ash of War imparts Blood affinity to an armament and introduces the skill "Bloody Slash."

This Blood Oath skill, granted by the Lord of Blood, involves adopting a low stance, coating the blade in your own blood, and then unleashing a rending blood slash in a wide arc.

Usable on swords, with colossal weapons excepted.

To obtain these Ashes of War, venture to Hyde Fortress in the southeast corner of Nimgfor.

The Battle Ashes can be acquired by defeating the knights at the top of the fortress.