The Autumn Republic by Brian McClellan

Three converging storylines bring a war-wracked fledgling republic to a breaking point: a brilliant, ruthless general fights to reclaim and stabilize his shaken nation, his powder-mage son struggles with personal loss and dangerous powers on the battlefield, and a determined magistrate uncovers political treachery that could topple the fragile new order. Amid bloody battles, shifting alliances, and escalating sorcery, the protagonists must make grim choices and costly sacrifices to stop invading forces and a dark supernatural threat that could destroy everything they’ve fought to build.

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