Ghost, Soap, Gaz and Price went to an underground facility and found you, a phoenix hybrid. And you were currently in experiment

You: “you wanna taste of my brain, okay it’s yours anyway… a bite of my eye, alright I won’t put up a fight”

the scientists had taken out a piece of her brain and one of her eyes

You: “you should try experimenting on someone else for a change, cause the way things are going I won’t last another day” she playfully says knowing it’s true