Board Thread:Speculation House/@comment-25574297-20141024020130/@comment-25396609-20150902220545

No, we won't.

The general consensus is that Yang saw Raven while mostly out of it, barely coming to after being knocked out.

She didn't actually see her face in the post-credits, it's pretty universally accepted that that was a dream sequence of some kind.

Raven is most likely some sort of spy or free agent, working within the WF, meaning she would be wearing the grimm mask to facilitate infiltration.