The Purity of Ignorance (The Horusian Wars)

While the Space Marines and the Imperial Guard fight the myriad alien enemies that seek to overwhelm mankind, the Inquisition pursues a different kind of war. For theirs is a war fought in the dark places of man’s soul – a battle against the corruption of Chaos, a battle for the survival of humanity. Inquisitor Covenant must hunt down the daemon at the heart of a planetary conspiracy, but how high a price will he and his team pay to defeat the evil, and are they even aware what the cost of success will be?

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Though he was introduced to the Warhammer 40,000 universe at the same time as Eisenhorn, there's never been fiction about Inquisitor Covenant... until now!