When she had shown him the changing of faces, it had chilled him to the bone. Donning a new face not only changed Arya's magical signature while wearing it, but he felt cold darkness slowly seep into it. The magic, if it could even be called that, felt vaguely familiar to the one of the Hallows, which did not bode well either. Death always gets its due, one way or another. He had attempted to replicate what she did, but with no success. It seemed that the ability was not trained but granted in the House of Black and White. He warned her heavily against using face-changing outside of dire circumstances. It seemed that just the sorcery that a faceless man used quite possibly changed the person at their very core, eerily similar to how the vilest of magics in his previous world did.