"Pieces continuously break away and reattach to the whole. Some shrink away into nowhere while giving the impression of getting closer. Others boil into existence and join themselves together. All give the sense that they belong to a single being, but you cannot find the connections between them. You feel heat radiating from the closeness of its flesh, from a direction with which you are not familiar."
I think a lot of people say they like Lovecraftian horror without fully grasping what makes a creature Lovecraftian rather than just "a monster". Like in the Call of Cthulhu tabletop RPG where having enough Int to understand what you just experienced makes it worse. If you can look at a thing and it makes rational sense in the physical world, like a giant humanoid with tentacles on its face, then it isn't Lovecraftian. It's not just that it's unknown, it's incomprehensible in the context of our reality. In Lovecraft's own words, "The Thing can not be described—there is no language for such abysms of shrieking and immemorial lunacy, such eldritch contradictions of all matter, force, and cosmic order."
The way they're presented in a lot of RPGs don't really help this. Giving any kind of Mythos being a stat block inherently violates the idea of it being some kind of incomprehensible horror, because now it's rigidly defined with numbers and words within the rules and context of the game.
"You cannot grasp the true form of Giygas's attack."
There's a post I've misplaced describing the comforting lie of seeing a "big squid." 'The most alien beast of the murky depths is our beloved brother compared to this.' They're not tentacles. They're veins. Or the substances flowing through them. Like if you reached into a two-dimensional world, all the inhabitants would see is a cross-section of things that shouldn't exist outside a body. And if you decided to trap one of them in a glass of water, or stick a pin clean through them, there would be absolutely nothing they could do about it.
From the other direction, there's that post about ants spelling out your name in sugar. It doesn't hold any power over you... but it'd certainly get your attention. You might do as they ask, because their desires are trivial. You might completely eradicate all traces of their colony. You know they don't belong there, but they cannot understand why. And if your flatmate's being a dick, you could instruct them to pick the lock to his room, while the ants don't even perceive the door as an obstacle. They're just ants, and they can walk right around it, on all sides. How could anything as freakishly powerful as you be restrained? They try not to think about it as they move these enormous gears and the whole goddamn world suddenly rotates around them. You'll surely be even more dangerous, once you've retrieved this immense artifact, your "PS5."
I would love if there were some eldritch entities that were chill or just ask you to do minor things to annoy another eldritch being. Not all of them need to destroy the world