User blog comment:Miskos3/Fairy Tail Episode 174: Four Dragons, Review/@comment-288216-20130323183432/@comment-1776824-20130324012718

Well, the counterargument to that is: in the manga, Sting's aura never faded; it remained constant throughout, until he entered Dragon Force. So, in conclusion, either the anime thought about making a fucking gigantic little change, they just forgot altogether, or they decided their budget is more important, which would explain a lot of the reasons for the quality as of late.