User blog comment:B214/Volume 22 spoilers/@comment-30329599-20170131213000/@comment-31137559-20170206230545

It would be kind of a downgrade considering the villains we have had so far. Ishibumi can save that for a sequel series. Because the way they sound, Malebranche would be no match against Issei and his companions or at least no match compared to the other OP opponents they have faced. 13 heinous criminals just appearing out of nowhere vs a tournament with gods and the most powerful people in the world competing where we can see bunch of epic battles and see how Issei adjusts to being king of his own peerage. I'll take the tournament. You think that was something Ishibumi would have put into the fourth arc. Rizevim frees the Malebolge and have them fight on his side. Again something for a sequel series. A villain in this arc would just ruin things and rob us of the epic battles to come.