Sorry if everyone knew but anyway think about it. The Exo Stranger in the Vanilla story wants you to destroy the black garden. WELL now it makes sense she's Vex! But why would she betray her own team? Well, basically it's like a time loop, if the Guardian doesn't destroy the Black Garden, they won't be powerful enough to defeat Oryx who will obliterate them so really, the Stranger works for the Vex because they were defeated in the future so learnt from their mistakes so went back and encouraged the Guardians to win.
Makes sense innit?
-
Is there a prove that the vex can timetravel? In my opinion they can seperate a "space and time" and control it. They control the matter in that space. Time flows only in one direction. But they need to take that space first, like the black garden. Or the vault of glass. They make simulations of the future. Thats all. Its even possible that a human gets simulated, (cloned). That simulation can control a exo body. Or even enter the vex information network. What is lost is lost,what changed had changed. but a exact copy of matter in a space can replace it. Copy the earth 2000 years ago atom for atom .... but only you in there and you have timetraveled .... but the universe around the earth not.