Omnispace.
The space around omni. The outside of the entire set-up.
Omnispace is one of the largest objects that are still physical. Most objects further would have to either be nonphysical, metaphysical or pataphysical.
It is the void that is located around usually the largest physical object, which is currently That Place. Only physical objects immune to Omnispace's properties surpass Omnispace. The rest will be thrown back inside and possibly shrunken. It is rare for an object to be immune to Omnispace.
Omnispace contains the majority of discovery. Nearly all of the discovered and known things in the First Realm exist here.
Omnispace.
While is contains nearly everything, the separator between objects is empty. Nothing. But it is a bit more than nothing. It is nothing. It is not nothing. It is absolute nothing. Except for a few spots that contain objects.
Omnispace is one of the largest physical objects, but definitely not one of THE largest in general. Anything metaphysical, pataphysical or nonphysical could easily escape. Most things, however, are physical.
Physical things, unless they have a defense, are always contained within Omnispace. Omnispace is the void. THE void.
Omnispace.