User blog comment:Ixarising/High School DxD Dream Battle/@comment-71.108.89.172-20140215205717/@comment-24468758-20140215232415

As of Vol.16 I would say it is Tannin's victory. Tannin is a former Dragon KIng with power equal to the Yondai Maou while Issei is "still" ultimate class in terms of power which is quite the feat in a bit more than half a year. With the dragon slayer power he would give him a hard fight but the old man is still stronger.