User blog comment:Dragoon leGreat/5x5/@comment-5209013-20121023113847/@comment-4623180-20121023115232

Wow!! Thank you for that!

They're definitely the three hooded old ladies we saw in the cave in the trailer.

Also

SPOILER ALERT SPOILER ALERT

I think that sacrifice may be

...

...

Mordred (but obviously something happens and he can't die, right? He was in that vision and he's destined to do something at the end), as I remember seeing on Livejournal someone who was watching the filming saw Arthur carrying an unconscious Mordred up a hill or something...