how

boo :ghost: congratulations you have found a candy for the trick or treat event! your prompt will be scary stories

“however, 500 years ago, the collapse of an ancient civilization turned the universe upside down...”

there’s several things in game that also hint to the geography of teyvat being upside down.

https://genshin.hoyoverse.com/m/en/map#

It might have come about because all the ruins of Khaenri’ah are usually upside down, so the ‘right’ way of the world as we see it might actually be the wrong way

Probably because of the theory about the sky being false and that the true sky is in the abyss