'The theoreticals always spoke of overwhelming Legio superiority, of war fought glorious, bright and gleaming under the swords of the righteous. The practicals of Calth have taught us that war against a brother can only be won by blood, bare hands and loss. The Legio will survive this. Must survive this. But the Thirteenth will be forever changed.
Praetor Tyron Auxentios, LCVII Company, XV Chapter, XIII Legio 'Ultramarines'