New idea and this will be very short.
- Another one with Chaos, but this one is far different. Chaos in this idea isn't a typical big bad, infact it isn't in the season until like right before the end. This is my idea somehow all the gates to Heaven, Hell, Purgatory, and even the other realms like Avalon are sealed. And it bring forth the true end this end is the End of all things, the time when God allows Death to reap him. However, before that the Natural Order states that that a destroy or creator to purify God's creations of all the true evils. However, as Chaos is originally pagan and not directly connected to God's plan and was made into the Natural Order latter, this can change. The other gods believe if they can control when Chaos arrives they will have the power to reshape the Universe and all it spiritual realms by their own desires.
- This is where Chaos comes in. I am taking the concept that in most Creation from Chaos creation myth, that believes Chaos was either a place, nothingness or vast endless seas of magical waters or material that would make creation and the first gods. Hence why many would view it as a god, espically if it could be sentient. So all this magical material becomes either the destroyer or creator of the end. If he comes as the destroyer. he will destroy all of creation including the spiritual realms, if he comes as the creator he will be the maker of God's original paradise, by removing only the really greatest evils. And despite being powerful God and Death are still stronger, and is why God has it planned for Death to reap him. As Chaos's plan is part of the Natural Order Death by his own policies will not interfer with it despite any issues he may or may not have with.
- I thought of as a way of explaining why Death believes he will reap God. And this is my answer, (in the fiction of the series not real life) That as God is all powerful, knowing and good, he wouldn't want to see his creation destroyed. So he would be revived latter by his own power, to either rule over the true paradise where Death doesn't happen. This way, without Death reaping anymore it basically like killing him or his purpose.
- As for the plot, maybe some of the older gods like more toward Atropos's age and older know of Chaos and are looking for ways to control it. After all it's powerful yes, but still shorter interms of powerful compared to God and Death.