We have seen the Fallen fight the Vex. We have seen the Cabal fight the Vex. But never have we seen the Hive fight the Vex. We know however that the Crota allowed the Vex to enter their dimension, and that they waged war against one another for a long time. We know that the Vex seem to want to be a force of the universe, from what I believe they want to be a literal law of physics. Oryx seems to also want to be a force of the Universe. So I would like to ask what you think. Why aren't the Hive and the Vex fighting? Personally I think it's because they literally have no reason to, they fought for centuries, that's enough to time to learn the others secrets. Oryx even admits that he had difficulty gaining control of that war. I wonder who the greatest threat really is.