User blog comment:CNBA3/Super Big Theory!/@comment-7418318-20131026210239/@comment-7418318-20131026223004

When Erza said that, she was so afraid I wouldn't have trusted her judgement if she said the sky was blue. Also with their ability to induce fear without any apparent reason, it's likely they can influence the mind of the victims directly, which makes the senses of the victims less trustworthy.

And the magic within the ice surely wouldn't give the ice more cutting power. A Demon who deserves to be called that should have thick enough skin that a frozen bush can't so easily cut through his skin. And apart from Retrogression Magic, what notable deed did you see Doriarte ever do?

A real Demon deserving of the name should also be able to do enormous damage with a simple fist-strike but neither both Gray and Natsu were able to take his punches even while weakened by his magic and weren't all that badly hurt.