[spoiler]Cortana is in control of a Halo Ring. SHEEEEEEEEIT. She has access to every piece of Forerunner knowledge, including the locations of all other Halo Rings. Cortana's plan is to activate Halo to wipe the slate clean of organics and restart civilization like the Forerunners did, except this time she's going to bend them to her will. CORTANA!!! Y U DO DIS? Y U PERSONALITY CHANGE SO SUDDENLY???[/spoiler]