Atheist

Well, any sort of discussion on the subject needs a god who follows thought processes which is expected to be understandable to us, otherwise there is nothing to discuss. The theist in the scenario can proclaim fideism, and that is an acceptable stance to take, but it does also prevent any attempts at theist rationalisations besides the actual fideism, and hence also any need for people to take heed for the fideists religious considerations.

It also asserts before any arguments that evil must definitely be an immutable force in the world

No, I don't see it doing anything of the sort.