Over the years and new additions to halo I have become confused for what Cortana was originally meant for.
In the prologue to halo 4 we see someone, presumably Halsey, giving Cortana to a depressed looking Master Chief. This reinforces the later idea in the game where Cortana says the UNSC will pair Chief with a new A.I., bringing us to believe that Spartan II’s always were paired with A.I.'s. That right there is a confusing idea as we know only Master Chief had been paired for a prolonged period with an A.I. In Halo: The Flood by William C. Dietz shows that it was the first time Chief and Cortana had worked together based on their interactions, and later in The Thursday War by Karen Traviss BB gets paired with Naomi. Naomi is not at all comfortable with the experience in that writing, obviously showing that Spartan II’s are not normally paired with AI’s.
Back to Cortana. In Halo Reach, Cortana’s sole purpose was introduced as Halsey’s helper in deciphering the giant forerunner thingy that supposedly leads to the Halo rings, and then she was carried to the Pillar of Autumn. This directly contradicts Halo 4’s prologue when Cortana was gifted to Chief, as well as the literature in Halo: The Fall of Reach, Halo: The Flood, and Halo: First Strike. In those 3 books it is expressly said that her purpose was to assist a spartan team in hijacking a covenant ship and using it to capture a prophet, thus negotiating a cease-fire. This mission is the same and only reason Cpt Keyes was given command of the Pillar of Autumn. Cortana is an expert at general hacking as we see because of this purpose in all books and games. Lastly, in halo: the fall of reach, it was stated that the UNSC found Halo’s coordinates from the artifact on Sigmus Octanus IV. This information was changed in the Halo wiki as leading to Reach rather than Halo to cover this contradiction. It is largely for these reasons I consider Halo Reach the game to be non-canon. This steal leaves a contradiction between Halo 4 and pre-existing lore, even you were to include Halo Reach the game.
So what which explanation is considered official canon?
A.) She was Halsey’s assistant on Reach with no prior contact to the Chief before Halo CE, rendering the prior novels and halo 4’s prologue and some of the ideas during campaign clips non-canon.
B.) She was created to assist the Spartan team hijack a covie ship, with no prior contact to the chief before Halo CE as well as rendering Halo Reach the game non-canon.
C.) None of the above, she was always paired to chief which screws with the general plotline
As I understand it, the Cortana we see in Halo Reach is a fragment of Cortana that contains the data of the Halo ring, which leads to its discovery after the Autumn takes off. The Cortana paired with Chief pre-Red Flag (Ackerson’s test) is the other part of her. When Noble team brought Cortana to the Autumn they reunited the fragment with the “actual” Cortana, and, well, you know the rest.
I’m not following your reasoning with the Halo 4 Prologue, though. Some things in it are obviously non-canon, like Chief and the rest of the Spartans wearing the armor Chief wears in Halo 4 during the Human-Covenant war. This is done so new players don’t get confused. I’d presume Halsey presenting Cortana to Chief was supposed to be a flashback to Reach and not a later thing.
Cortana was created from Halsey for Operation: RED FLAG, due to her extreme hacking abilities.
A Spartan needed to carry her on the mission, and she chose John. They were tested together by Ackerson. Cortana was then entered into the Pillar of Autumn, but a fragment was left behind to work with Halsey on the artifact on Reach. Once completed, Noble Six was chosen to take her to the Autumn to be reunited with her other part.
I am confused how there could be multiple fragments of cortana when she hadn’t discovered replication technology until she dissected the covenant AI during the events of First Strike, after Reach fell.
I can accept that the two were tested beforehand, despite how the two interacted during halo: the flood. This could explain the prologue theoretically.
And now for the basic synopsis, this combines all contradictions of canon into one…
Cortana was of course, created by Dr Halsey with a cloned brain. Her purpose was to serve as the spearhead of intel for OPERATION: RED FLAG
But before Red Flag could be executed, the Covenant began their invasion of Reach, but the ONI had also found a collection of Ancient Artifact’s that could hold the key to survival.
Since Cortana excelled in the art of hacking, she was fragmented into two halves that would be able to gather the data from the Artifact’s. The first half was stationed on the Pillar of Autumn as a temporary Shipboard AI, and the other half was in possession of Dr. Halsey during the excavation of the Babd Ice Shelf.
But as the ultimate fall of Reach loomed ever closer in the horizon, the other half of Cortana stationed at Sword Base had to be reunited with the rest of Cortana to unlock the Artifact’s secrets.
This is where NOBLE TEAM came in, they were assigned by the UNSC ARMY to destroy Sword Base, but the true purpose of the mission was revealed. With Reach now on it’s last planetary breath, Spartan B312 of NOBLE team was assigned to transport the fragment of Cortana to the Pillar of Autumn.
In this final mission, all of NOBLE team was killed, but their victory was not. If NOBLE had not succeeded, they would have not found Halo, who’s coordinates were stored in the Artifact, and humanity would have been swiftly annihilated.
> I am confused how there could be multiple fragments of cortana when she hadn’t discovered replication technology until she dissected the covenant AI during the events of First Strike, after Reach fell.
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> I can accept that the two were tested beforehand, despite how the two interacted during halo: the flood. This could explain the prologue theoretically.
Certain scenes in the prologue are non-canon and purely used as a quick representation of the Human Covenant War.
Cortana was fragmented, not copied or cloned. That means her processing power is split into two.
> I am confused how there could be multiple fragments of cortana when she hadn’t discovered replication technology until she dissected the covenant AI during the events of First Strike, after Reach fell.
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> I can accept that the two were tested beforehand, despite how the two interacted during halo: the flood. This could explain the prologue theoretically.
Because it’s not the same thing. It’s not a copy of Cortana in Halo: Reach, it’s a fragment that’s been “sliced” off of her subroutines. It wasn’t even anywhere close to a full AI, the fragment was pretty much just suited for data mining the Forerunner artifact, and that’s it. Unlike with what Cortana did on Unyielding Heirophant where she was spewing infinite clones of herself all over the station’s systems. It’s not the same technology and not something that she could just decide to spontaneously do herself, someone other than the AI had to be the one who cut the fragment out until it was reunited with the “real” Cortana.
And shouldn’t be taking the prologue as rock-solid canon, because that’s not what it’s meant to be. It’s meant to be a casual immersion into the basics of the last trilogy, both as a refresher for old fans, and as a way for the newer fans to get their feet wet, as it were.
I don’t think there’s ever been an implication that all Spartans would house AIs. Before receiving Cortana for the first time, John-117 specifically had his neural implant upgraded for the task. There’s no mention the rest of the Spartans underwent a similar procedure and probably had their regular implants at induction.
Then there’s also the issue of canon. In the books Pillar of Autumn was in space leaving the system when the Covenant attack. In game they hadn’t left yet