Soul of Nadalia, Bride of Ash
This soul is available in the Crown of the Old Iron King DLC. It comes in twelve fragments and must be pieced back together to become whole. To do this, all of the Ashen Idols in Brume Tower must be destroyed with Smelter Wedges and the Fume Knight must be defeated.
This particular soul can be traded in to Straid of Olaphis for the Outcry Pyromancy or to Ornifex for the Chime of Screams.