Hollowverse

A Hollowverse is a Universe, if we can even call it that, which is an empty shell. Its ontological barrier is the only existing thing, which appears to be a bubble separating it from the Interdimensional void.

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There isn't much to be said about the Hollowverse, as it is merely an invisible roaming shell of a once Universe. It is incredibely rare to find any sort of information written in these, aside from the obvious "I am a lonseome barrier. My grasp used to confine such visual wonders, alas, my host is forever gone now" that is encoded in a sort of Reality-encoder, but is translatable to concepts and equations.

For some beings, they can interact with the bare bones of a Hollowverse, like if it bore any significance alike to that of an actual Universe. These beings use the Hollowverse either as a mechanical part in a machine, home "island" of sorts, and some more uses.