Shadow Games by Glen Cook

In the aftermath of northern wars, a battered mercenary brotherhood marches south in search of its legendary birthplace, led by its hard-bitten captain-annalist and accompanied by a deposed, now-mortal sorceress. Drawn into the politics of a river kingdom threatened by the enigmatic Shadowmasters, they rebuild their ranks, navigate treachery and shifting alliances, and wage relentless campaigns, edging toward a decisive confrontation that could shape their destiny and rekindle old powers.

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