Athame

Had they the slightest understanding of the thing’s true heritage and what it was capable of, it would have been under lock and key in their deepest, strongest vault pored over by their finest minds until they ascertained how to use it, not merely left on a plinth in a museum on a world populated almost entirely by artists.
...
+The athame. If it can part reality surely it can carve through daemon flesh?+ she replied.
+The knife is attuned to the warp so in theory, yes it could do that.+



Prelude/Chapter Sixteen