User blog comment:IamJakuhoRaikoben/Chapter 433 & 434: Ikusatsunagi & Demolition Fist, Review./@comment-24546844-20150511182459/@comment-7418318-20150511204424

I didn't think of Mystogan, because that magic circle/formula/symbol reminded me of Amaterasu. Though due to no one other than Hades ever useing Amaterasu, I was quite sure Arlock was a new character rather than a hidden old one.