What is a Metamultiverse?

First, a little background.

Worlds
In Pixel Space, there are several named divisions of space. The lowest that matters here is worlds, singular spaces within Pixel Space that, although most are infinite, exist within Pixel Space as a whole without taking up too much of the space, for reasons explained later. These worlds generally fit a theme or revolve around a character type, and most (but not all) have names. This theme can vary wildly between worlds, and characters who know a world well enough from either an entry or exposition by another character (if another character shares a world’s entry, this can be both) can cross over to that world using Unaligned as detailed in the Skill List for that Power Type. Some Metas involve other works as worlds, referred to as "non-Pixel worlds" and these worlds are under what's known as a Secondary Framework so that the rules of that work can still apply to that work but only to that world and its characters.

The Multiverse
n Pixel Space, there exists an alteration of the Many Worlds theory that effectively means that every world has every variation of itself (for instance, different versions of characters) inside its own multiverse. These alternate worlds are referred to as Alternate Universes (or AUs) and the original is referred to as the “prime”.

The Metamultiverse and Onward
Finally, the Metamultiverse is the collection of the multiverses of all worlds in Pixel Space, which is why it’s called that. It’s the multiverse of multiverses. The Metamultiverse isn’t all of Pixel Space, however, and there are alternate Metamultiverses with different rules, designated in entries with the letter R and the number designating the order that Meta was revealed in. For instance, there is one where respawning isn’t something that all Pixel characters do. Then there is the group of all Metamultiverses, which is not currently named. Then there is the group of those, and so on and so forth, outwards infinitely. The culmination of these groups is what is all of Pixel Space, which is why it was created in a different reality than the one the creators lived in. A simulation would not be able to run the entire thing as efficiently as needed, and the other dimensions that would have existed in the reality the creators lived in would not be the ones needed to put Pixel Space into one.