The Death Company is the terrible answer to the curse that lies coiled within every son of Sanguinius. When the psychic echo of the primarch's murder at the hands of the traitor Horus erupts in a battle-brother's mind, he ceases to know himself, believing in his final hours that he is Sanguinius reborn upon the field of his death. Such warriors can no longer be reasoned with or recalled, and rather than waste their loss the Blood Angels gather them together, strip and repaint their armour, and give their madness a purpose.
Those taken by the affliction are clad in black, marked with a red cross that recalls the wounds their angel suffered in his last battle, and hung with parchments recording the honours they won before their reason failed. Chaplains lead them into the fray, for only the iron faith of a spiritual leader can steer such broken souls, and men like the Guardian of the Lost march at their head to shepherd them toward a death that carries meaning. In their final charge the fallen feel neither fear nor pain, striking with a strength born of absolute despair.
To the enemies of the Blood Angels the Death Company is a nightmare given form, a howling wave of black-armoured giants who cannot be stopped by wounds that would fell any ordinary warrior. To the Chapter itself they are a grief and a warning, a living glimpse of the fate that may one day claim every one of them, and each brother lost to their ranks is honoured and mourned once his last battle is done.