Otherselves
In the Fire world, seventeen-year-old Leah is the illegitimate daughter of one of the realm's most powerful lords. She's hot-blooded—able to communicate with the tempestuous volcano gods that either bless a civilization or destroy it. But then Leah discovers she's a Caller, gifted with the unique—and dangerous—ability to “call” her Otherselves in mirror worlds. And her father will do anything to use her powers for his own purposes.