I have a theory that involves the Arbiter Thel’ Vdaam. His main weapon is the prophets bane. If you look closely in the spartan Locke armor gamestop trailer you can see Thel’ Vadaam in the background with the prophets bane in hand. and it even makes sense. prophets as in the covenant hierarchs, witch he tore down. He was the bane. bane means to ruin or spoil. It all makes sense.
That wasn’t the Prophets’ Bane. It was blue. That wasn’t the Arbiter. But the name of the sword is obvious to the meaning.
I thought the name was pretty obvious… And I’m pretty sure that’s not the Arbiter since the sword isn’t gold
Though the sword isn’t blue it has the same shape. (This is just a hypothesis)