The Battle of Sarosh

Sarosh was meant to be a triumph of the Great Crusade's patient diplomacy, a jewelled theocracy brought willingly beneath the Imperial aquila. Instead the Battle of Sarosh became a lesson in how faith festers into damnation. The Sons of Horus walked into the marble halls of the Saroshi hierarchs expecting oaths and celebration, and found instead a hidden priesthood that had bargained with the powers of the warp long before the Emperor's ships ever crossed their sky.

When the treachery came, it came in fire and unnatural shadow. A summoned horror tore through the compliance delegation, and the Warmaster's warriors fought a nightmare that iron and bolt shell could barely wound. In the confined splendour of the hierarch palaces, transhuman warriors were flung aside like children, and only discipline and cold fury held the line long enough for the daemon to be banished back into the abyss that birthed it.

The world could not be suffered to live. The Sons of Horus, their pride wounded and their dead uncounted, withdrew to the void and delivered Sarosh unto cleansing flame. Whole continents of the faithful were rendered to glass, and the survivors carried a bitter knowledge back into the fleet: that the enemy the Imperium truly feared did not wait beyond the stars, but coiled within the hearts of those who prayed too fervently to gods that were never silent.