Many ontological proofs of the existence of God, consider God to be a supremely or maximally great or perfect being (see for example, \citealt{Oppy_2018b}). For example, the proof of St Anselm considers God as a being “than which nothing greater can be thought”, where greatness can be in qualities such as omnipotence and omniscience. Assuming both the unlimited possibilities for evolution in a potentially infinite number of universes and the plenitude principle, then maximal greatness on a scale such as the Karadashev scale ought perhaps to be achievable. The maximum may be set by the physical properties and laws of the universes involved. Unlimited possibilities may however imply not only an indefinitely large number of maximally great entities but also a multitude of minor gods at various stages of advancement. This could be in line with religions which have many gods. Perhaps one way to generate a single God of maximal greatness would be to imagine a process of merging within this multitude of gods constrained by whatever physical laws could be operational within the multiverse in relation to interaction between universes and the gods they contain.
Could the belief in a God that has emerged naturally and inevitably in an eternal existence of multiple universes be consistent with or acceptable to major religions or religious perspectives or practice? Could this belief be tolerated? Is it strictly necessary to believe in a supernatural God? Given the great diversity of religions, could belief in a naturally emerging God be subsumed into the totality of religious belief? Perennialism emphasizes the underlying unity that the similarities between religions disclose, and that the one God in revelation is impartial, evidenced by long-term survival of the great religions (\citealt{Smith_1987}). From this perspective, to rationalize belief in a naturally emerging God, emphasis could be attached to the similarities between this belief and the beliefs of other religions, rather than on the differences.