User blog comment:B214/Volume 23 discussion blog/@comment-81.135.248.15-20170321190507/@comment-10330822-20170321194451

1. Asia's actually more likely because of her aura mixing with Fafnir, it makes her more dragon-like and thus better suited for a Dragonar armor.

2. Yes, Ajuka implied that if Issei can get Ophis and Lilith working together, it would aid him in being able to control his DxD G form without side effects. The AxA is said to be hinted if Issei keeps fighting, meaning it may surface during the tournament. The ExE form will mostly likely come after the tournament, near the end of the series. We don't know if Dragonification will come into play, because Issei can already turn himself into a dragon, he just can't control it and he can't go full dragon mode. Ideally, a merged form of Dragonification and Boosted Gear, similar to an Abyss Side for ExE, would be the best of both worlds.

3. Vali probably wouldn't be in this tournament, unless they relax the requirements for their duel. Cao Cao and Sairaorg would probably be decided elsewhere, same with Diehauser. Indra I feel will be the god Issei firsts manages to defeat. As for the tournament itself, its highly likely it wouldn't even finish. Rias will be a combatant though, because Issei wishes to prove himself a worthy King and a worthy fiance for her.

Besides, if Issei plays Rias, he essentially fights Crom. That will ultimately be what the fight is, because besides Vasco, no one else on that team competes with Issei 1-on-1, and Vasco is a stretch now that Issei has his DxD forms.