In the Shadow of Mighty Wings: Ha-Mashchi: Blood Angels Destroyers

Within the spheres of the Blood Angels, there exist outsider elements. Marines so damaged by war or those who are unable to work within the reformed tenets of the Principia Belicosa, that they may only find refuge in their own, unstable kind. These are not the formations of the Angels Tears, those who commit acts of lawful atrocity, and who may lay their burden aside once the act is complete. Those few who comprise the Ha-Mashchi are permanently damned by the proscribed weapons they wield.

Rememberancer Taihij; The Numbering of Angels. 

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