User blog comment:- Darkchylde/Acnologia's Element?/@comment-173.87.12.242-20141211055642/@comment-7418318-20141214122330

Even if some Dragons betrayed him, it still doesn't justify him trying to wipe out the entire species.

And him not attacking anyone for seven years isn't much of an argument for a being that measures his life-time in centuries. What are seven years of dormancy for someone who's lived for more than 400 years?

He could have done anything from sleeping to wiping out entire countries on another continent that's just too far away or maybe even completely unknown to the people of Ishgar and thus the news never reached Fiore.

Considering how much he hates Dragons but still didn't turn up during the GMG when the other Dragons appeared, him being very far away actually makes a lot of sense.