Posted by: IScout SniperI
I'm not too much into this, but I see a lot of people asking why Cortana isn't in Marathon if Halo and Marathon are the same. (which I don't think they are)
Here's your explanation besides "Well, Bungie hadn't thought of her or Halo yet, that's why."
In Fall of Reach, it says Cortana can only last nine years. It says it when Chief receives her and his new model armor (with the Covenant-based energy shields).
At the end of Halo 3, he goes into cryogenic sleep. Marathon and Halo are 200 years apart. He might wake up during Marathon, but Cortana will be gone. She can only stay for 9 years before she effectively dies.
That explains why Cortana isn't in Marathon, if they are indeed the same universe.
Which I doubt they are.
Well, actually, she doesn't die, but instead goes rampant. Leela?