"This is not a demon but a kind of god transformation, to transform into the shape of gods." Eternal Peace Imperial Preceptor was used to this sight and explained to Hu Ling'er.
He naturally could see that this wasn't Qin Mu revealing his true form and was a peculiar technique instead. It seemed to be the effect by merging a few techniques of Heavenly Devil Sect together.
"It seems to be Spirit Creation Technique merging with the Mars Technique of Five Elements Realm…"
He had little knowledge about Great Educational Heavenly Devil Scriptures so he wasn't too sure.
Qin Mu's body shape-shifting was considered god transformation and some techniques could achieve that as well. It wasn't rare and it was one type of body divine arts.
The techniques of some sects specially relied on god transformation and devil transformation to upgrade their bodies.