Scarred by the Impure

Scarred by the Impure was a lamentable event that occurred during the latter years of the 39th Millennium, when the Imperial world of Alexandria, the Chapter homeworld of the Argent Blades Space Marine Chapter, was devastated by an overwhelming attack conducted by the infamous Black Legion Traitor Legion. During the vicious fighting, some of the Argent Blades' battle-brothers lost themselves to the violence of the battle - losing consciousness - and unleashing devastating slaughter upon their foes. Though the Chapter emerged victorious, it was a hollow victory at best, for once again some of their own had begun to show worrying signs that were unbecoming of an Astartes. Despite extensive investigations, the Chapter's Apothecaries were unable to determine what caused such savagery to be released.

History
Towards the end of the 39>sup>th Millennium, the Argent Blades were engaged in many conflicts across the sector and beyond its edges as the Orks terrorized the Kolleshian Sector. As the chapter purged each world of the taint of the greenskins, they were pushed further away from Alexandria. The Argent Blades were alerted by the Master of the Watch, desperately calling for reinforcement. When the 2nd Company arrived as the spearhead of the fleet, the world was in flames. Dropping to the surface like valkyries from the heavens, the Argent Blades fought in the streets of Alexandria against a warband of the Black Legion. Witnessing the impurity they wrought upon the beautiful cities of Alexandria, the Argent Blades flew into a rage. Each company fought with the fury of a Primarch, gunning down anything that dared to stand against them and burning the remains.

Even after the warband's defeat was certain and their fleet blown from the void, the Argent Blades massacred the cultists and Chaos Space Marines. Their disgust at the impurity wrought by the Black Legion and the anger they felt for the destruction of Alexandria caused some among the Blades to lose themselves in the fight. Blacking out and awaking covered in the blood of the heretic and a boltgun aimed at them by their suspicious brothers. These marines were rounded up and given a chance to defend themselves for their impurity, but were then shot nonetheless. The already suspicious chapter took the fate of these marines to heart. The Chapter Command began an investigation into what had caused their impure and savage actions. Officially, there was no evidence that could be found showing why this had happened.