User blog comment:Omega natsu2/Chapter 371: Tartarus Arc, Part 2: Song Of The Heavenly Dragon, Predictions./@comment-77.194.131.108-20140207103647

one of the fairy tail members will activate a power which was sleeping inside him / her and protect everyone from being killed, but not injured ( my bet on Lucy ), Zeref will appear because Natsu has been imprisonned but will change his plans. Maybe it's the situation described on this famous draft, Mashima never stated when this situation will happen, and maybe changed his mind and put ti here now