User blog comment:B214/Volume 21 info & spoilers/@comment-26345952-20160711012832/@comment-24.113.252.213-20160711030851

Well, in Vol. 22 Issei and Diehauser are participating in the "International Tournament". So we might get to see another Issei vs. Diehauser fight.

Hopefully all our questions on this topic will be answered:


 * Would [Penetrate] work on Diehauser?


 * Would DxD mode wreck Diehauser?

I honestly think DxD mode would leave Diehauser in the same state it left Rizevim (almost dead).