The Cold Commands by Richard Morgan

Haunted by past wars and a brutal slave trade, a caustic swordsman, an embattled imperial advisor, and a weathered steppe hero follow diverging paths through political treachery and encroaching otherworldly menace. As zealots tighten their grip on a faltering empire and inhuman forces stir behind the veil, they hunt buried technologies and strike perilous bargains that test loyalty, identity, and survival—threatening to unleash powers capable of remaking their world.

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