Warhammer 40k Horus Heresy Nemesis

"(W) James Swallow After Isstvan V, Horus declares outright war against the Imperium. In the shadows of the Emperor's Palace, powerful figures convene. Their plan - send a team of assassins to execute the arch-traitor Horus and end the war for the galaxy of mankind before it has even begun. But what they cannot know is that another assassin is aboard already, with his sights set firmly upon killing the Emperor."