Inheritance Trilogy Series by Jo Zebedee, Teresa Edgerton, Sam Primeau

First book in the trilogy. Author, Francis Knight said. "A bright and fresh new voice in the genre, brimming with imagination, subtle worldbuilding and engaging characters" "Everyone has a plan to use Kare. His cruel mother, the Empress, demands he accepts his position as her only heir. His father's rebellion want a figurehead to stand against her. Kare just wants to avoid the horrific future foretold for him."