The savage dawn - Melissa Grey

The sides have been chosen and the battle lines drawn.

After awakening the firebird, Echo is now the only one with the power to face the darkness she unwittingly unleashed upon the world . . . right into the waiting hands of Tanith, the new Dragon Prince. Tanith has one goal in mind: destroy her enemies, raze their lands, and reign supreme in a new era where the Drakharin are almighty and the Avicen are nothing but a memory.

The war that has been brewing for centuries is finally imminent. But the scales are tipped. Echo might hold the power to face the darkness within the Dragon Prince, but she has far to go to master it. And now she's plagued by uncertainty. Is she strong enough to stare into the face of evil and not lose herself in its depths?
The war has begun, and there is no looking back.

There are only two outcomes possible: triumph or death.