User blog comment:B214/Talk About What You Want! 2/@comment-99.196.4.193-20141022222148/@comment-120.161.1.143-20141023185751

I can see kiba as an ultimate weakness for issei in the future. He could create Dragon-killer swords and if he somehow manages to increase the skill of his troops so they can fight like himself, oh yah Gram is also effective against dragon, no ?. So Issei will be in a lot of troubles once kiba could master his potentials.

I bet Cao-Cao right now will be hundred times more dangerous compared when he was in Vol 12. The only weakness Cao-Cao has is his "half-assed" attitude, Vali once said that Cao-Cao should have killed him both with Issei, when he got the chance to do so. Imagine what he can do if that "half assed" attitude taken from him right now.