Halo Infinite releases this holiday season, which will pick up the story of John-117, the Master Chief, after the cliffhanger ending of Halo 5: Guardians. Some Halo novels have filled in some of the gaps between Halo 5 and Halo Infinite with another novel specifically focused on one of Chief's post-Halo 5 missions coming out this September just a few months before the release of Halo Infinite.
Regardless of whether fans have (or will) read any of the Halo novels, there are some big questions that remain after the conclusion of Halo 5. These are questions that will hopefully be answered in Halo Infinite.
Is Cortana Still Cortana?
In Halo 4, Cortana is starting to experience rampancy, which is the end of her age as an AI. Rampancy is "linked with the AI developing a longing for godlike power and contempt for its mentally inferior makers." By the end of Halo 5, Cortana believes she and other AI are the Reclaimers and have the right to rule the galaxy and bring it under control to impose peace on all living things. Despite saying that she was healed by coming into contact with the Domain, Cortana still seems to be experiencing rampancy. So one of the big questions is if she was actually healed or if she is still rampant.
Similarly, is the question if Cortana is still herself. Did coming into contact with the Domain change her or allow someone or something to interact with her and take her over? Perhaps the Cortana in Halo 5 is not Cortana at all, at least not the Cortana that players have come to know over the years. To take this theory further, there was a secret audio file found within the "Discover Hope" E3 2019 trailer that sounds like a much less hostile Cortana saying "This...this is part of me. I don't know why. I don't know how...but it is me." Perhaps she was split somehow in Halo 5 and Chief is still trying to recover the true Cortana in Halo Infinite.
How far has the Flood traveled?
The Flood were not present in Halo 5: Guardians, but in the Halo Wars 2 DLC Awakening the Nightmare, the Flood returned; the events of which occurs in the present timeline around the time of Halo 5: Guardians and Halo Infinite meaning that the Flood are still present within the galaxy. And with Cortana disabling as many civilizations as possible with EMP attacks throughout the galaxy at the conclusion of Halo 5, that seemingly puts untold numbers of living populations at risk for an invasion from the Flood.
Developer 343 Industries has not revealed if the Flood will be in Halo Infinite, but it is a very relevant question to wonder how the Flood will take advantage of the current situation of the galaxy and how far they could have traveled in the time between Halo 5 and Halo Infinite.
What are Dr. Catherine Halsey's motives?
Dr. Catherine Halsey has always been an enigmatic character in Halo, whose motives are never quite clear to anyone but herself. As the one who created Cortana and the Spartan program, her motives could very well be on a collision course with the other characters and events of Halo Infinite. This September's Shadows of Reach novel will send Master Chief and Blue Team back to Reach "to penetrate the rubble-filled depths of CASTLE Base and recover top-secret assets locked away in Dr. Catherine Halsey’s abandoned laboratory—assets which may prove to be humanity’s last hope against Cortana."
So, while Halsey seems to be on the side of Master Chief, the UNSC Infinity, and humanity, it seems she always has a surprise up her (now-empty) sleeve and her own self-interested motive in every situation. Her fate and influence will be a question Halo Infinite will hopefully answer.
Halo Infinite releases holiday 2020 for PC, Xbox One, and Xbox Series X.