I haven't really posted anything about this before, so I figured I should. This is just a general infodump about the Conglomeration, the multiverse setting for pretty much all my characters, even Ridley so much as I use his backstory any more. It's an idea I've had in some manner for about 15 years, though I never worked on it in any great detail.

The Conglomeration consists of millions of universes bound together in a vast structure.
These universes are incredibly varied; within them you can find Star-Wars-like galactic civilizations, medieval fantasy worlds, simple wildernesses, and everything in between. They are connected to each other through a web that carries magic throughout the Conglomeration. It is possible to travel between universes within it either by portals, teleporters, or interuniversal ships. For some worlds, such travel is as commonplace as a going to the airport. For others, travel between universes, while not impossible, is basically unheard of and the denizens are unaware that their universe is just one of many.
The space between universes is not entirely void either; magic flows through it, and it is inhabited by higher-dimensional lifeforms.

Magic is a fundamental component of this multiverse, right alongside matter and energy. It is present in all worlds within the Conglomeration at least a background level, even in seemingly non-magical settings, though it is not always tangible. Some worlds are rich in magic with things like wizards, magical beasts, and enchanted forests. Others are seemingly mundane.
As well as being present in the environment, magic occurs within living beings. Like tiny reflections of the Conglomeration, magic flows through them. For many it is simply there, and plays no real role in everyday life. Some, though, are able to use this magic. Hence, we have magical beings such as dragons, kitsune, and unicorns. Humans, who are strangely ubiquitous in the Conglomeration, are a strange case when it comes to magic. In their base state, they have no magical abilities, but some people or populations have gained them in a variety of ways. They may have been exposed to concentrated environmental magic, granted abilities by a god or other powerful being, or may have had a non-human ancestor. Once a person gains the ability to use magic, it may or may not be heritable. A hodgepodge of gods exist throughout the Conglomeration, shaping various worlds to their liking. Some magical beings came from these gods "uplifting" mundane creatures; for instance, kitsune were made from ordinary foxes and dragons were made from much smaller winged reptiles.

The Conglomeration itself is alive and has a consciousness, which regulates the flow of magic on a grand scale. This consciousness does not take part in the lives of the denizens of its worlds though; it does not even perceive them any more than you perceive the activity of your cells. It does know that the worlds within it are inhabited.

I did come up with something of an origin for it as well. The Conglomeration was created by the last gods in a cold, dying universe out of a desire to see life continue. It grew like an embryo from the remains of this dying universe, both by forming new universes and incorporating others that happened to be "nearby." One or more of these first gods became the consciousness of the Conglomeration to guide this process. (This last bit, as well as the name "Conglomeration" was inspired by the Doctor Who episode "Utopia," which came out around the time that I first conceived this idea.)

The image is a sort of representation of the web of magic, with windows into some of the worlds. Most of the images used here are photos I took. A few (the ones showing planetary rings and a double sunset) are scenes rendered in Space Engine, a virtual planetarium created by Vladimir Romanyuk. One image in the lower right is part of the Hubble Ultra-Deep Field, courtesy of NASA.