User blog comment:Renkrisb/The Dragneel Brothers/@comment-26416024-20150519215248/@comment-26416024-20150525020733

Making E.N.D. not as strong as he is said to be would be the biggest mistake Mashima could possibly make with the series. If he is not that strong, than Tartarus should not even bother unsealing him and just hope Momento Mori is enough to kill Zeref. Plus Atlas Flame was around back then. And of course, Natsu wasn't ready to kill him on Tenrou Island. He still did not have his powers. Sorry, but I can't agree with what you are saying.