So I honestly cannot for the life of me remember where I had read it, but I am pretty sure that if I remember correctly, there is 2 AI versions of Cortana that Halsey had made prior to the events of Reach.
My speculation and according the recent rumors or leaks – master chief and blue team are on Reach or going there so to speak. Why? Perhaps they know something lies in the ashes of a once prominent research facility? Hope.
Cortana has reached relentless power and soon dominance of the Halo universe as we know it. But what if the only way to beat her is by fighting fire with fire? You cant use any other AI to go against her but what if its against her own DNA counterpart that there is actually a chance?
This could explain too why from the teaser trailer we got a while back that chief has a empty AI chip. Perhaps this actually takes place mid game on the way to Reach as a placeholder for the new AI? OR even after the events that could transpire on Reach and it was stolen from chief explaining why hes drifting away in space from a destroyed ring with all power in his suit cut due to a lost battle? MAYBE even new Cortana did it on accident?
Whose’ to tell its all theory. I’m a huge nerd for the possible so what do you guys think? Am I wrong on any of the potential specifics or tie ins? Let me know!