Hello. I’m currently developing the framework of a class based game that revolves around the usage of different fictional gods which I made up myself (for instance, I made a character called Helio, the sun god). I just don’t want to finally upload it and have Roblox slap a ban on my 2013 account.
I’ve seen multiple games that have used mythological characters as themes for their games and no action has been struck against them so I’d say go for it!
Just a note: when giving people responses on whether something is allowed or not, I highly recommend staying away from “others do it and they’re fine” logic to justify anything at all. This isn’t a sound argument; action not being taken does not implicitly mean it’s allowed.
In OP’s case however, fictional deities and such (or otherwise mythological or overarching characters) aren’t against any kind of rules. I’d strongly encourage staying away from any kind of detailed and thorough religious themes as per the Terms of Use, but otherwise they should be fine.
The gods in my game have small “backstories”, but it’s really just explanations of their power in a way that isn’t boring. There’s no morals taught or anything.