In the imperium's darkest hour of need, these phantom marines spring forth from the warp, skulls leering and bolters spitting death. Their hate for the enemies of humanity is unending, and the will unbreakable. Striding across the battlefield they shred the xenos and heretic alike, shrugging off blows that would bring even a space marine to their knees. Even when their fiery forms are finally brought down, they rupture in a final inferno to ensure that their defeat is never without a heavy cost.