User blog comment:IamJakuhoRaikoben/Chapter 382: Alegria, Review./@comment-7716957-20140428163152/@comment-4829046-20140428174642

I might be going bonkers again, but that statement made me feel that Lucy's escapade would result in something great and might trigger Natsu's Dragon Force at some point of the Tartarus arc, so yeah, in a way, she might save Natsu. I believe Lucy would be the key to bring END and Zeref down.