User blog comment:B214/Question and Answers 2/@comment-187.209.0.247-20140319182450/@comment-24468758-20140319184512

Even boosted attacks won't work since they are enhanced by a sacred gear so the attack would just be cancelled. I think Vali will find a way to use sacred gears against Rizevim and kill him himself or with the help of Issei (this may even work without the sacred gears).