>>15816839Different fag, but... The idea is that not every crack led to oblivion. That's why Amy was able to pull things out of them. It's like the fish lady said, only SOME lead to darkness and the death of all things, whereas the other fissures lead... other places.
The theory is that there's a civilization on the other side of the cracks and that, now that the cracks are closed, their only connection to the real world is Amy, who is of course special because of her affinity for the cracks. I kind of doubt it because I think Moffat probably dropped the cracks storyline.