When we saw Cortana in Halo 5: Guardians, she was threatening to destroy anyone in the universe if they opposed her. Her rampancy had grown out of control, and it was clear Master Chief would have a tough battle ahead of him. However, we never got to see or experience anything of Cortana's conquest, as Halo Infinite begins a few years after the events of Halo 5.
Although it's revealed that Cortana perished off-screen before the majority of events in Halo Infinite, that doesn't mean Master Chief no longer has an AI companion. Another AI was developed by the UNSC to combat Cortana, codenamed simply "the Weapon," and she is clearly the key to helping Master Chief fight against the Banished and rescue the remaining UNSC marines on Zeta Halo.
Updated May 30, 2022, by Amanda Hurych: Halo Infinite's release date has come and gone, but that has not stopped fans from pondering on the Weapon's character and what her future in the Halo universe will be. She plays a pivotal role in the game, but not much is known about her background. What little we do know now has been added!
7 Her Name Is The Weapon
While she looks and tries to act like Cortana, she is her own AI construct with a different name. At the beginning of the game, Master Chief needs to retrieve a weapon of some sort to even the odds against the Banished. Echo-216, the UNSC pilot who only wants to go home, expects a massive gun of some kind, but instead, the Spartan returns with this AI program.
The UNSC created the Weapon to assist the Chief in exploring Zeta Halo and finding the actual Cortana. However, it's revealed that Halo Infinite takes place a few years after the events of Halo 5, so Cortana is no longer a threat. Throughout the entire game, the AI is explicitly referred to as "the Weapon," but before the credits roll, Master Chief asks her what new name they should call her, and it's a safe assumption she will pick up the mantle of her predecessor.
6 Clone Of Cortana
As Master Chief and the Weapon are uncovering more of what happened to Cortana, it's revealed that the Weapon is simply a clone of Cortana. She's still her own AI construct, but this explains why she's so similar to Cortana in virtually every way.
Throughout Halo Infinite, it's clear that the Weapon acts similarly to Cortana, too. She's quirky and doesn't mind speaking her mind with the Spartan. She can be quick with jokes or criticism, depending on the situation. While she's not the real Cortana, she does operate incredibly well under pressure and saves Master Chief on numerous occasions.
5 She Is Voiced By Jen Taylor
Jen Taylor, the actor who has been portraying the character of Cortana for over 20 years, returned to voice Halo Infinite's Weapon. Hardcore Halo fans will be able to pick up on her iconic voice right away. It sounds like Taylor altered her voice to make the Weapon sound a bit younger and more naive as suits this new AI.
While she doesn't sound exactly like Cortana, her optimistic personality could be credited to her recent creation by Dr. Catherine Halsey and the UNSC who developed the AI for this specific mission. Whatever the case, Taylor does a phenomenal job conveying the difference between both versions of Cortana.
4 Her Mission
The Weapon was designed to help Chief find Cortana, secure her, and lock her down. In Halo 5, Cortana became a threat when she planned to use the Guardians to achieve imperial peace. Unfortunately, the game ended without a concrete explanation of what happened to her. Many players expected Halo Infinite to tell the story of Master Chief having to fight against his long-time companion, but instead, the game picks up after those events have already transpired.
After Master Chief retrieves the Weapon, she remembers that Cortana has already been deleted, so her mission has been completed. She instructs Master Chief to delete her, but the Spartan informs her that the mission has changed, and he needs her help to defeat the Banished on Zeta Halo.
3 Her Deletion Was Halted By Cortana
After locking Cortana down in the Silent Auditorium, the Weapon was intended to auto-delete. Her purpose fulfilled, the UNSC did not want to risk another "Cortana" situation occurring down the line, so having the Weapon eliminated after she served her function was the logical course of action.
However, when Cortana got trapped by the Weapon, she realized that her actions on Zeta Halo threatened all life in the galaxy. Wishing now to assist the Master Chief in saving humanity once again, Cortana stopped the Weapon's deletion program from happening so that when Cortana sacrificed herself, the Master Chief would still have someone like her to help him.
2 Takes Responsibility For Cortana's Actions
For much of the game, the Weapon doesn't appreciate the fact that Master Chief is so unwilling to trust her, given how much she's done for him since she's been activated. She's saved the Chief and Echo-216 countless times already on Zeta Halo and continues to show her resourcefulness in locating other UNSC marines in danger while seeking out high-value Banished targets. However, it's not until she discovers what truly happened to Cortana that she understands why Master Chief was reluctant to trust her.
When the Weapon finds out about Cortana's rampancy and her history with John-117, she begins to truly see why she was important to Master Chief. She understands what she meant to him and how he takes responsibility for what she did at the end of Halo 5. The Weapon promises that she won't become like Cortana, but Cortana echoed the same sentiment about not succumbing to rampancy. Regardless, the Weapon seems to take responsibility herself for what her predecessor did and assures Master Chief that she will do whatever is necessary to keep him safe and complete the mission.
1 Rocky Relationship With Chief
Throughout the Halo series, Master Chief and Cortana have had a strong relationship. They trust each other, they've grown together, and they would fight for each other. Whatever the case, fans cannot deny these two have a powerful bond. However, Master Chief doesn't share the same type of trust for the Weapon — at least, not at first.
Chief appears a bit hostile toward the Weapon for much of the first half of the game. He gets snappy with her when she says Cortana has been deleted and even a bit angry when he asks if she did it. She can sense his bitterness and is a little uncomfortable, yet she tries to defuse the tension by smiling and being friendly toward him.
Even as Master Chief begins to trust her, he's quick to activate the deletion protocols at one point, indicating that the Spartan won't try to save her as he did with Cortana. While Chief is understandably wary of an AI resembling his closest companion, they still have a mission to complete, and he is willing to cooperate with her.