I don't really know the answer to this question. I mean with feats laxus should be stronger but people in here also says that author's intention and portrayals matters. Until mashima states who's stronger between s12 and BDSM. If you think about it laxus should be stronger than a human form dragon god cuz he defeated kirin who's stronger than suzaku based on statements, but the problem is mashima doesn't think this way. If dragon gods are equal and suzaku defeated human form selene why was he fodder to ignia and dog? Is laxus also stronger selene human form since he defeated kirin? Mashima doesn't think like this for mashima once two characters are said to be equals they'll be equals until mashima states otherwise