A compelling fantasy debut with rival sisters and intricate magic

A River of Royal Blood introduces the princess Eva, born with the magick of blood and marrow, a dark form of magick last practiced centuries ago by a cruel queen. Eva approaches her 17th birthday on which she must battle her older sister Isa to the death for ascendency to the throne of the Queendom of Myre. Eva is attacked by a mysterious assassin, and turns to a fey mage who can instruct her how to control and practice her magic. There are four peoples in this book: humans, the Fey, the Khimaer and the Bloodkin, which make for a fascinating society and mythology. I liked the character of Eva, who is not interested in playing politics and empathizes with those around her. Tensions and action escalate and there is a big twist near the end. World building is well crafted. It looks like there is going to be a sequel, which is welcome news to readers of this book.