See I figured the codes would just make the ending easier. Also thought it was going to be a double cross or something, like he wanted the Archon out of the picture so he could do what he wanted. When I got to the part that asked if I wanted to use it or not I sat for like 2 minutes going over what could happen. Then I figured if the game gave me a choice now to save it then it must be useful later. When I saw ol boy looking off in the distane at the end I was so happy I kept it. Figure he may be a part of the DLC or something.