Thank you for reminding me how much I enjoyed Battlefield. “Just between you and me, Mordred, I'm getting a little tired of hearing about your mother.”
It was SO much fun. Too many good moments to mention. ♥

Consciously-chosen by River, I mean. Obviously deliberate by Moffat too, but it means in-story as well as out.
*tilts head* Unless River had an invisibility cloak/spy cam how could she possibly know?