This Ash of War grants an armament the Occult affinity and the following skill:

"Spectral Lance: Skill of the headless Mausoleum Knights. Hurl a phantasmic spear at foes."

Usable on polearms (reapers excepted).

The ashes are located in the Academy of Magic, from the Chapel of the Blessed Cuckoo.

Leave the church and continue through the cemetery into the Academy of Magic.

Cross the suspension bridge to the location shown in the picture below, then turn left and enter the path on the left.

The battle ash can be obtained by killing the dung beetles on the path.