J.M. Briggs 
The Iron Cursed [EPUB ebook] 

Magic can’t fix everything. The war with Scáthbás and Arthur has claimed the lives of Alex’s parents, and there is no end in sight. While the Fae are freed from the power of the Iron Chain, plenty of them blame the mages and the Iron Soul for their enslavement. At night, Alex relives her deaths and memories from her other lives. It is only a matter of time before something breaks.

Leugio never planned on becoming involved with the mysterious Sídhe, who lived in the mount near his village, but when his sister vanished, he had no choice-yet saving her thrust Leugio into the war brewing on the horizon. With no help in sight, he must protect Ireland from the growing Sídhe threat.