LOL. OK conspiracist, I'll see you that and raise you Erevi is really Qetesh in hiding. Where better to hid?
Conspiratist? If Nergal is this universes version of Satan you don't think he'd advance his cause with lies? gather some powerful followers, leashing them by making them believe that HE is the source of their power?
All Gods are the same
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claiming credit for the good shit that happens around them, blaming the bad stuff on that other god over there.
My earlier post about them being like two PvP players wasn't just a joke, almost all mythologies have the "gods" playing their games with mortals, manuevering them, gathering them, they may be powerful beings, but power is magnified by belief, ask any conman.
The Game of thrones touched on this with the Red Priests.