Vanquished (The Elder Tree Trilogy #3) by Erica Eberhart:
 
Through the darkness there is light.

Queen Greer must resurface from devastating grief and prepare for war with the fae king of Invarlwen, Malcolm. Shifting through the motions of her duty, she battles growing resentment toward magic makers for destroying a piece of her heart. She sets her conflicting sights on her sister Caitriona, who struggles with her own losses, as both a danger and someone to protect.

With newfound determination and self-discovered power, Caitriona insists on finding Ailith, missing since falling into Kayl’s magical necklace. Against Greer’s wishes, Caitriona absconds through magic portals to new lands with hope of saving the woman she loves.

Beyond the mist, Ailith battles her own demons as fae are transformed into monsters forced to serve in Malcolm's growing army. Facing the threat of forced servitude, she strives to find the strength she doubted in her magicless self.


In this thrilling conclusion of The Elder Tree Trilogy, Greer, Caitriona, and Ailith fight to reach the light through the dark without it breaking them, leaving readers entwined in their story of love, sisterhood, and bravery.