Ashen remnants housing lingering spirits.

Utilize them to invoke the spirits of three colossal rats.

Spirits that necessitate no FP for summoning.

These rat spirits manifest at a distance from the summoner, swarming their target to initiate the battle.

Even in their spectral form, these pests seem to propagate endlessly. Augmenting these ashes can amplify their numbers.

The ashes can be located in the windmill pasture on the western side of the Yatan Plateau.

You'll discover the ashes on the corpses within the cabin.