User blog comment:B214/Volume 23 discussion blog/@comment-77.188.244.180-20170422150942/@comment-1.10.198.77-20170422170257

Issei is abnomal person and already made a lot of ridiculous things.

he manages to overcome Riser, Shalba, Loki,  Sairaorg, Cao Cao,  Euclid, Rizevim, Barakiel despite being outclassed massively in term of experience.

even Crom Cruach have trained himself for thousand of years, he is not invincible and can be defeated.

In battle, nothing is certain.