User blog comment:B214/Volume 22 spoilers/@comment-95.90.227.198-20170101172200/@comment-10330822-20170102015034

Yeah, Indra is the leader of the Devas, so he, in terms of hierarchy, is below beings like Vishnu, Brahama, and Shiva. Shiva, as the God of Destruction, would logically be the strongest Hindu God.

I also don't quite know if Indra is weaker than a Heavenly Dragon. What we do know is that a Super Devil as a class can be below a Heavenly Dragon, since Rizevim was weaker than that class, but Sirzechs and Ajuka maybe just as strong.

We know Ajuka and Sirzechs are top 10, but we don't know where. My guess is that they are stronger than Hades and probably quite a few of the gods. We just need more information honestly.