The Bondsmagi of Karthain are an order of sorcerers who wield genuine magical power in a world where most people consider magic either myth or irrelevance. Based in the distant city of Karthain, they hire out their services to the wealthy and powerful for exorbitant fees - a single Bondsmage can turn the tide of a war, collapse an economy, or destroy a rival with terrifying precision. Their guild enforces a strict monopoly on magical practice and responds to any attack on its members with overwhelming, disproportionate retaliation, making them feared across the known world. Despite their power, the Bondsmagi are bound by their own internal politics and factions, and their interest in Locke Lamora and Jean Tannen draws the Gentleman Bastards into conflicts far beyond the scale of their usual cons.