I misread 12 as 15. But the blog post says you pick three images. So 12 choose 3, or 220. OK, if you were willing to sit through their video, why don't you

I misread 12 as 15. But the blog post says you pick three images. So 12 choose 3, or 220. OK, if you were willing to sit through their video, why don't you tell us about this second layer?