The complete Ignite Series by Erica Crouch.

Includes:
Ignite, Entice, Incite, Engage, and Infinite

IGNITE
Pen fell from grace over a millennium ago, yet there are still times she questions her decision to follow her twin brother, Azael, to Hell. Now that the archangel Michael has returned, threatening Lucifer’s vie for the throne, she begins questioning everything she has always believed. 

ENTICE
Suddenly top-tiered demons, Pen and Azael are tasked with seeing through hell’s new agenda: corrupting man. But tarnishing Eden isn’t as simple as they thought it would be, especially when they’re forced to work with another team of demons who are trying to claw their way up the ladder of power. A novella that prequels IGNITE.

INCITE
Earth is in ruins, and the war of Heaven and Hell has spilled over into the mortal world. In the frozen wasteland of the apocalypse, Azael and his band of cohorts search for Pen and Michael with orders to kill. Little does he know that his sister has incited a rebel army of her own. 

ENGAGE
With a mass cleansing on the horizon, Kala discovers she is not alone in her insubordination; there are other angels who are restless with the stasis of Heaven and ready for change. Progress doesn’t come easily, though, especially when it means uniting ancient enemies to fight for a common cause.  A novella that prequels INCITE.

INFINITE
As Azael spirals deeper and deeper into darkness, and Pen grapples with her new leadership role, a familiar name rises to power whose decisions have the potential to rewrite everyone’s future. Dangerous secrets, silent traitors, and unraveling fates means that time is running out. There’s no telling who will survive the final battle.