"Ghost's analysis suggests this weapon has been exposed to incredible forces...and that parts of it shouldn't yet exist." So what if the key to unlocking the Fate of All Fools was in the Vault of Glass? The Stranger's Rifle contains parts that shouldn't exist yet, plus is aesthetically identicle to the Fate of All Fools. Since parts of it exist only in the future then it makes sense that the Vex play a part in the equation. The second part of this might be the Pocket Infinity. "You cannot shake the feeling that this is less a weapon than a doorway." It is a possibility that equipping the Pocket Infinity might open a doorway during or after the Atheon fight. Just food for thought. I plan on doing a Vault run with the Strangers Rifle as my primary, a Pocket Infinity as my special, and a Hezen's Vengeance as my heavy.