Cain's Last Stand (Ciaphas Cain Book 6)

After a long and distinguished career defending the Imperium from its many enemies, Commissar Cain is enjoying a well-deserved retirement on Perlia, teaching in a schola progenium. But when a Black Crusade threatens the sector, all able-bodied citizens must rise to the defence, including Cain and his cadets. As the forces of Chaos overwhelm Perlia, can the wily commissar prove himself to be a real hero of the Imperium one last time?

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This entry from the Cain Archives takes the Hero of the Imperium into his greatest – and possibly last – battle. He's an old man in this one, pulled out of retirement for one last mission as the hordes of Chaos close in on the Imperium...