The Spellslinger - A Fistful of Daggers, #4

Lincoln Marshall has failed. The Godslayer is trapped in her worst nightmares. His only chance of repairing the timeline is dead. He's stuck a decade in the past with Sophie Keyes, and the world is falling apart. Held captive by the Union, Lincoln and Sophie must fight to repair a timeline rapidly unraveling. James Faulkner has survived, but he's not whole. He's divided into angel and demon--his ambition and obsession severed from his power and passion.
His angel side wants to rescue Elise. His demon side wants to rescue the world, at any cost--even if it means letting Elise die. Between their brilliant minds, they've conceived a plan that can repair the timeline. The only price is their lives. Book four of the A Fistful of Daggers Series by New York Times Bestselling Author SM Reine.