It was a legendary time.
The Great Crusade brought the light of the Imperial Truth to the darkest corners of the Galaxy, returning scattered human worlds to the bosom of the Imperium and erasing alien races from the face of history. By the will of the blessed Emperor, who decided to step away from warlike affairs, the command of this unparalleled campaign was entrusted to Horus, the primarch of the Legion of the Luna Wolves.
That’s how the chronicles speak—but nowhere in them will you find an answer to the question of when, beneath the sky of which world, the seeds of the Great Heresy took root. Maybe it happened on the day Horus killed the Emperor for the first time…