Crowned by Grace White

Finally able to access Gaia’s memories, Terra learns the truth behind the darkness currently swarming over Atchison College. But one question still remains.
Who is Tartarus?
With time running out, Terra and her four protectors enlist an ally to seek the answers they don’t have, and desperately need. But Terra knows their efforts are in vain. Because there is only one way things will end. And although Sol, Cael, Ross, and Endo refuse to accept it, Terra is ready to do whatever it takes to save Earth.

Even if it means the ultimate sacrifice.