The Oathbreaker's Shadow by Amy McCulloch

Raim has waited all his life to become a member of the elite patrol called the Yun and dedicate his life to protecting the Khan and the kingdom of Darhan. He does not know his parents since he was abandoned and fostered by Loni, a man who has become like a grandfather to Raim. The only memento he has from his early life is a promise string tied around his wrist, but Raim has no memory of making a promise to anyone.
Something disastrous happens on the day Raim should becoming a Yun, and he is forced to flee Darhan and seek some answers.
I enjoyed this book, and will definitely read the conclusion (The Shadow's Curse). I especially liked the originality of a promise sealed with a knot, and having powerful magic protect that promise from being broken. (Imagine if such a thing really existed! People might take their promises more seriously)

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