User blog comment:- Darkchylde/Acnologia's Element?/@comment-173.87.12.242-20141211055642/@comment-173.87.12.242-20141214174920

i doubt he can sense when other dragons are around. if he could igneel Grandeeny and metallicanna would be dead to wouldnt they i mean the people(civilians) who were there had no idea what happened. I also think that the same spell that made acnologia a dragon is what made zeref immortal and there lives could intertwined and acnologia doesnt kill zeref because if zeref dies he dies and he doesnt wanna die leaving something as dangerous as END around