User blog comment:B214/Question and Answers 4/@comment-24098614-20150214225932/@comment-1359322-20150215015058

I guess i'll join in the topic. First off, Diehauser is Maou-class, probably he's as powerful as Serafall and Falbium. Next we have Sirzechs, a Super Devil, and is 10 times stronger than the original Lucifer.

Moving on, there's their ability. Diehauser's ability to nullify a clan's trait. Sirzechs' ability which is an insanely powerful POD that can annihilate and from what we seen during his brief fight with Ise, Sirzechs can also negate attacks probably using his POD.

So in the end, it depends on which ability is stronger, is Diehauser's nullification more power or Sirzechs' POD that can both annihilate and negate attack in more powerful. The rest, you think on your own.