Maybe something maybe nothing

But I'll just leave this here at 0.24 second point

http://youtu.be/5GWUhxr7cCA

Just coincidence. Obviously ravens have a folklore connection with the Tower of London, and they also have a place in Norse mythology (so tie-in thematically to Ashildr).

http://fandomania.com/wp-content/upl...ckguardian.jpg