From Black Library:

Rogal Dorn, Primarch of the Imperial Fists Legion, faces a stark reality ­ he must tear down the magnificence of the Emperor's Palace, a shining beacon in a galaxy of darkness, and turn it into a fortress. With the army of Horus drawing ever closer, as he blights the Palace with gunports and defence towers, Dorn must face a difficult question, "What are you afraid of?"


Complete Audiobook

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