I was doing research on Joyeuse and I read that its hilt was forged with the Holy Lance. If you are not familiar with Biblical stories it is the spear that stabbed Jesus Christ. Another name for this artifact (the spear) is the "Spear of Destiny". Many forum users know about the theory that involves AI and swords. This could be a key link in what Joyeuse really is. It is both a weapon and an answer just like the AIs of the previous trilogies. If this really holds up then Destiny is Joyeuse and Joyeuse is probably our ally or something equivalent to that. We are literally fighting with, for, and to protect Destiny. Ad Astra. Edit: Cortana Five brought up a good point. At the end screen of Marathon: Infinity it says "YOU ARE DESTINY". I think that there could be a correlation between this and the possibility that we are actually defending Joyeuse since Durandal said it. It would make so much sense if we used the weapon and either the Traveller or the queen was Charlmagne (especially since he was a king and we have a queen) or even us somehow, but that seem less likely.