The Chronicles of the Unbinding: Hazard's Price

Every spy has a past. Every man has his price.
 
Long ago, a brutal war between the countries of Chaldus and Yndor left the mages with blood on their hands. To rid the world of destructive magic, they performed the Binding and vowed that never again would a magical war be fought upon the land. But the Unbinding has begun.
 
Someone is killing former Chaldean ministers and leaving a unique calling card: a gold coin in their mouths. Galatine Hazard recognizes the sign, because once it was his own trademark. He’s a respected man now, but someone is setting him up. To clear his name, Hazard has to reach back into his bag of tricks to catch the killer, a wily assassin who could bring the country to the brink of war and unleash the power of the ancients.