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The character is, she might be a clone. Honestly, it makes some sense, she can activate artifacts, the Covenant would want to keep her alive.

Although this does mean the same is true for John, so he's the last person ONI should want to be rid of.

I somewhat retract my earlier comment re kill death ratio, the character is referring to an in universe game called Spartan Attack, although it's still a really silly comment, on seeing a giant military person to immediately ask for their kdr in Call of Duty still doesn't make sense.