There are three final questions that all deal with needs:
11.What is this society's most ardent need?
12.How does it go about satisfying this need?
13.What would it take to disrupt normalcy on this world?
11. What is this society’s most ardent need?
No society is ever in a state of perfect balance for longer than a microsecond. Figure out what the biggest need of that society is, because it will greatly affect its values and evolution. Does it need energy to fuel its increasing numbers (like we do)? Does it need new hunting grounds because the old ones aren’t fruitful anymore? Or maybe it needs genetic diversification? If the need for expansion is desperate enough, you might have a very aggressive society on your hands that won’t fidget long before invading new territories at great costs. Or maybe your society needs to sort out an internal problem like corruption, disease or dependency?
The Aliens' needs are beyond our comprehension. Why do they do what they do, what drives them, what need are they trying to fulfill? We will probably never know.
What is our greatest need; we little folk of Earth? Hiding will do us no good, nor will knowledge. Do we have any hope of attaining the kind of intelligence or power of these other civilizations? Homo sapiens certainly does not. We have neither the longevity nor the mental capacity to reach any level of technology higher than perhaps K level I or II.
Transhumans, or the emergent AI that develops from the AI we birth through the singularity may rise to that level. Make no mistake, they may rise to a level where they can understand these god-like aliens. Rising to the level where their needs are something like the needs of the aliens is highly unlikely. There is no way to tell what is on the other side of the singularity, at least not for humans on this side of it.
I do know because I am the omniscient author do know. We will ascend through a melding of genetically enhanced transhumanism and technological AI. The two will become one and move forward to take our place as one of the lowest, weakest, mentally deficient of the star traveling races. Our descendants may even return through time to perhaps themselves be inconceivable god-like aliens.
12. How does it go about satisfying this need?
The way a people tackles a problem or tries to satisfy a need says a lot about its nature. Is it trying to build or fight its way out of the trouble? Is it willing to risk something else of value? Is it canibalizing its resources or managing them sensibly? Is it indiferent to how it affects the environment or other societies / species? Does it shift its collective attention to evolving past the point of the need in a positive direction, or does it focus on eliminating the problem by any means necessary? Does it think long-term or is it short-sighted?
Now, after you’ve created a basic structure for your world, before you drop your characters into it and let them fend for themselves, ask yourself one more thing. It might help you use that wonderful worldbuilding to strengthen your plot.
There are a few things we can witness whether we understand the needs of the aliens or not. Some of their needs are satisfied here on Earth and/or with humans. There are some of their needs that require the use of humans, or at least lower sentient beings. Some of them (the Extrinsic Ones at least) derive something from our pain, fear, panic, anxiety, anger and despair. Some of them are roughly the equivalent of Vogons, with complete apathy toward what to them is merely a slight impediment along the path to whatever it is they want or need.
Much of the terror of our situation living in their universe is that we have no way of satisfying the ultimate need we have of living peacefully, of understanding even a part of what these great races want from us, of having even the slightest chance of avoiding whatever fate they decide for us, or even when they have no consideration at all for us, and our fate is doomed regardless. We can't begin to start to satisfy our greatest needs; thus ending all hope and giving way to ruinous devastation for those who even barely understand what is really at stake.
The rest of us can live in blissful ignorance, until our planet is ended with a proverbial bat of an eye.
13. What would it take to disrupt normalcy on this world?
And I’m not talking about the moon crashing into the surface of the planet, or the ground cracking open and unleashing a geyser of demons into the world. I’m talking about what a single individual—your protagonist—can possibly do that is so disruptive that it turns him into enemy number one? Now how can you drive him to do just that, unwillingly or unavoidably? And what happens next?
Ah, here's the rub. The moon crashing into the Earth, or the ground cracking open and spewing forth unspeakable horrors is exactly what could happen. What could my protagonist do to become the worst human who ever lived, someone so vile that Stalin and Hitler would cringe, cry and hide? Simply seek some of the knowledge of the Great Alien Races, attempt to commune with them, accept allegiance with any that bother to contact us. Collaborators, scholars, cohorts, devotees, conspirators, worshipers, and supplicants are all supremely dangerous because they are tapping into powers and knowledge that will rip them and all of us apart, often physically and minimally emotionally, spiritually and mentally.
There you have the 13 worldbuilding questions. Honestly I don't feel like this fleshed out my horror universe. Perhaps it didn't because so often authors don't really give the universe a proper scale. The universe is one world often. It is one land and maybe two peoples in conflict. The whole of the universe in the books and stories are there to serve the characters and their venue. The focus is orders of magnitude less than what the real universe is. This is fair enough. In reality what do any of us care about the explosion that caused the Horse Head Nebula? How much can a supernova thousands of light years away affect us?
But in my universe these do matter and they do affect us. In fact they are but tiny pin pricks in the vast power and destructive capacity. These things are coming to get us, by design or through negligence and there is nothing we can do about it. We may or may not be lucky enough to realize they are on the way before we all die in the most horrible, painful and demoralizing way possible.