Weeping angles.
[img]http://media.tumblr.com/a4bb6dd238263ac17d5ea7d567a063fe/tumblr_inline_mmpx26We8x1qz4rgp.png[/img]
Weeping angels.Do you want them to freeze only when someone is looking directly at them or when they're in anyone's field of view.Should they freeze when ANYONE sees them or only if they're in the same minigame?