The Fruit Of Dark Tides - Among You Secret Children, #2

'Be in your death! Now! And fight with the dead! Pass through the ones you kill like deer leaping from the mist, and you will land in the day. You are in the heart of your life, and your heart is beating you, and you are here to kill death which is our enemy.' Fleeing the chaos of a runaway fire, Moth and Jaala take separate paths that find them aligned in a struggle to defeat an elite corps at Nassgrube attempting to create a monstrous new race capable of overrunning the earth. But with Moth's air supply failing and Jaala struggling to round up an army of surface-dwellers, the time to act is fast running out.
It seems the only way to survive is to undergo life-threatening changes; that and the summoning of a vicious and long-dead tyrant. The Fruit Of Dark Tides is the second book in the Among You Secret Children trilogy by Jeff Kamen.