User blog comment:Jopjopjop/Volume 18 Spoilers/@comment-3965848-20140715170854/@comment-24982259-20140715174653

Nope, I doubt it's the final Volume of the 4 arc, since I doubt that Rizevim  ... one of the three Super Devils that exist in the DxD universe, would be defeated, just becuase his nulification ability dosen't work on a single ability that Ise has recently gained...

It would actually be a pretty anticlimatic way  to end this arc as well.

Personally, I doubt that this arc is going to end, until Rizevim gets to the place where 666 has been sealed by the God of the Bible and the entire DxD team move after him, in  order to stop him.

After all ... considering the ways in which most of the previous arc's have ended ... Ishibumi is usally ending his arc's in a pretty climatic way (usally by providing us with a quite big and cllimatic battle) and for this arc ... I can't think of anything more climatic then the entire DxD team vs the entire team that Rizevim has created ... along with adding a partially unsealed 666 beast, to spice things up and give some pressure and time limit to the good guys side...