hellfire lava

I stepped forward as another wave of ghouls bounded over those the gunfire had held off.
Murphy and Marcone had bought me time enough for the spell I'd been forming in my mind to meet with my will and congeal into fire. I whirled the staff overhead, and then brought it down gripped in both hands, striking its end to the stone floor as I cried, "Flammamurus!"
There was a crackling howl, and fire ripped its way up out of the stones of the floor. It rippled out from the point of impact in a line running thirty or forty yards in either direction, a sudden fountain of molten stone that shot up in an ongoing curtain ten or twelve feet high, angled toward the ghouls charging us from the far side of the cavern. Blazing liquid stone fell down over them, among them, and the oncoming tide of screaming ghouls broke upon that wall of stone and fire with screams of agony and, for the first time, of fear.
The wall held off fully half the ghouls in the cavern and screened us from Vittorio's sight. It also provided all the humans with plenty of light to see by.
"Hell's bells, I'm good," I wheezed.
The effort of the spell was monumental, even with the Hellfire to help me, and I staggered, the light vanishing from the runes of my staff.


White Night Chapter 40, Page 428