The Ash of War imparts Quality affinity to an armament and introduces the skill "Vacuum Slice."

A lost skill of ancient heroes, it involves holding the armament aloft to envelop it with a shearing vacuum, then launching it forward as a blade-like projectile.

Usable on swords and axes, with colossal axes excepted.

To acquire these Ashes of War, explore the basement where the treasure chest is located.

Follow the road from Blessing, turn right at the pavilion, and enter the room on the right. Discover the ashes on corpses within the room.