Ashes of the Witch by Lucas Pederson

SPFBO8

Slain by her enemies, Gorecrow makes a deal with DEATH. Six days until a trapped god is freed. Six days for vengeance. She must travel through the dreamscapes and nightmares of her enemies searching for the god she lost and entrusted to keep while quenching her lust for blood. The only things standing in Gorecow's way are the Shifting Lands, an extraordinary girl, and utter madness.