"And that's not the worst of it, I'm afraid," Twilight said, getting finally to the hardest part. "They're looking for something specific. You see, they can sense... I'm not sure how to describe it, but they call it a ripple. It's where part of another reality brushes up against our own. Do you know that there are other realities out there? Different worlds, some similar to ours, others completely alien? Did you know that?" 