She Is The Darkness by Glen Cook

Amid a grinding siege of Overlook, a battle-scarred mercenary brotherhood presses its campaign against a ruthless Shadowmaster while treachery and Taglian politics tighten the noose behind them. The annalist Murgen, haunted by a death-goddess and gifted with unsettling ghostwalking visions, spies on foes like Soulcatcher and Mogaba even as the loss of his family and prophetic nightmares erode his stability. Sorcerous duels flare, old rivalries fester, and brutal ingenuity defines the fighting as the siege grinds on. The struggle hints at darker destinies ahead, steering the Company toward the mysteries of the Plain of Glittering Stone and a fate none of them can clearly see.

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