Ghost in the Machine

The players of SAO heard of the legendary Black Swordsman and feared him. However, there was an even more frightening entity in the world. Nobody knows where he came from, what he really looks like, aside from his blue hair, or even what his abilities are. The blue-haired 'Ghost in the Machine' is not a player, not an NPC, and not to be trifled with. (Being re-written)