Positive assertion therefore provide the proof that it is fiction.
Your positive assertion is that God is a real thing.
My positive assertion is that you have provided no evidence that such a thing exists objectively (as in "true for everybody else and not just me") anywhere outside of your own head.
Let's see how that stacks up, Vladdychops. If you want me to point you to literary sources that Iago and Sauron are fictional evil characters, I can very easily do so. If you want me to point you to literary sources that God is an evil character, I can do so with equal ease.
You think that 2 out of these 3 are fictional while one of them is objectively real. I say you haven't even come within the same continent let alone postcode of demonstrating why I have to take your fairy tales seriously.
Burden of proof, burden of proof ...