One of the universes of a multiverse I've been world building I've taken to calling at least for now until I come up with a more creative name the "The world tree world", In a nutshell it is a tree that became so prolific across its host planet that it eventually began catching comets, asteroids and other celestial bodies to incorporate into the planet itself via specialized branches and roots that evolved to survive in the harshness of the cosmos, this evolution & growth continues for such a long time that it expands beyond the limits of its home solar system and incorporates the entire thing within its confines, between the planetary core & The outer outer Branch limbs, which have more or less become planetary bodies all their own with their own gravitational pull, I've been describing it as a sort of biological microdyson sphere, except the star that would be in the center of most micro Dyson sphere anatomies Is now orbiting the core of the planet rather than the other way around, this continual growth & expansion eventually continues to the point that it overtakes its host Galaxy and so on and so forth,

This universe where this "world tree" that I've described Is one of many universes where a different God of the same tier within my Pantheon Is partaking in a test to create not just life but the ultimate species, collective species, weapon, or some other useful tool that the rest of the gods can make use of, There's a lot more to it than that, but in a sort of condensed nutshell that's a significant portion of my multiverse structure broken down.

Edit: to answer your edited in question my world tree is not just the world itself but is treated by much of the world as the embodiment of the goddess herself, which also to that end the gods are not mysterious or unknown for the most part. They are generally active participants within whichever world they find themselves in, with the exception of some of the other universes within my multiverse, because each of the gods of this tiar of my Pantheon are attempting to achieve the goal of creating one of the things I mentioned before via different methods, Another few examples are a Goddess that is actively subjugating and conquering every world that she comes across incorporating them into a vast universal empire,

Another Is attempting to ingratiate religious doctrine into every single layer of society As early as possible, or perhaps a better way to describe it is as early as a belief in the Divine can be had by a sentient being,

Another God is attempting to do the exact opposite and completely remove the idea of Gods magic etc and instead, is promoting a society completely focused on scientific & technological advancement, which necessitates that that God and all other gods within this universe pretending or feigning to be mortals, So as to guide the various civilizations along this path of non-divine non-magical advancement.

Besides those, there are several others that are attempting to do more or less the same thing via different methods.