Player Domains

There are worlds out there, completely unlike the standard fare. They still seem to operate on the same principles as more common worlds, but they each have an element of flair that feels ... I don't know how to rightly describe it. More personalized, perhaps? Like there is something distinct overseeing that world as compared to the greater multiverse. I don't know ... maybe I'm just confusing myself.
-Starstrider's Notes

Once a player has reached a Divine Rank of Intermediate Deity and completed 8 or more approved adventures (see We are the Voices), the player has permission to request a Domain.
In a few words, a Domain is a world that you have full creative control over. You don't need any special permission to add details to it - it's yours, provided your world otherwise follows the rules of the game itself. Out-of-character, this takes the form of a personalized forum space under the Domains category. Characters may freely visit your Domain by Corridor and consider it part of the greater game world, including purchasing homes, running adventurers, and anything else an adventurer with 'the Spark' might do in a given adventure setting.
You can think of your Domain as its own campaign environment, complete with whatever BBEGs and world events you want, provided you keep the following details in mind.

Location, Location, Location

All Domains are located in Realmspace. There are no ifs, ands, or buts about this. Your Domain is in the material plane. This means that it has its own overlapping feywild and shadowfell, connects to the various transitive planes, and is subject to the competing influences of Order, Chaos, the Positive Plane, and the Negative Plane. How that distribution falls ends up at your discretion, but that's a separate point.
Once your Domain has been created, players (and by extension, their characters) are free to come and go from your Domain as they please through the Corridor, including using your Domain as a home world for their own characters if they wish. NPCs on the other hand can only travel to and from your Domain if they have the means to do so within the game's rules: spells like dream of the blue veil, successfully navigating a sequence of color pools in the Deep Ethereal, or sailing across the stars in a Spelljammer are all examples of how NPCs may come or go from your world, if at all. Keep these thoughts in mind as you build your Domain.

A Pantheon

You may create up to three deities of your own to serve as your Domain's pantheon. Just like our characters, the gods you create have no idea they are extensions of your narration, and carry on with their lives as any god would. Whether you create your own deities or not, the gods of the greater Pantheon of the Chromanexus exist in some fashion, even if diminished in your world's lore.
Regardless of what you create, remember that a deity's purpose serves as a means of giving your world shape and structure through their belief systems. They are otherwise far removed from mortals and by extension, our characters. This also means that even among your own deities, direct communication with mortals should be exceedingly rare, if not impossible. Gods communicate through other mediums and intermediaries - visions, omens, priests, etc - which alone are often left open to interpretation, for better or worse.
Should you reach a rank of Overdeity with 30 or more approvals, you are permitted to submit your world's deities to join the Chromanexus Pantheon, permitting you to begin referencing them elsewhere in the Overworld and in other player's Domains.

Echoes of Chromatia

The world of Chromatia is the most important world in existence, for reasons we won't dig into right now. The important thing to know is that every other world in realmspace has a distant connection to this place, with overlapping timelines and curiously similar events. While the story of your Domain remains at your discretion, the legends and myths of Chromatia have a tendency to pop up in their own ways in your Domain. How that happens is up to you.
For example, the Riders of the Apocalypse exist in Chromatia. They are harbingers of the end of times, which is fitting given the apocalyptic state Chromatia often finds itself in. While the Riders themselves may not necessarily be present in your Domain, their legend certainly does, even if only in far flung corners of the realm. Creatures that call themselves great wyrms might exist, sharing similarities with the powerful great wyrms that call Chromatia home, but they are not quite the same nor do they have the same power.
This also means that the ongoing apocalypse has at least some shred of influence in your Domain, as it effects the entire multiverse. Even in the most peaceful domains, it is not unheard of to discover the occasional abyssal rift in the past few decades, prompting adventurers to rise and repel the invasion. How widespread the invasion is in your Domain, however, is otherwise at your discretion.

Your World

Provided you follow the rules of the game itself (including Chromanexus's House Rules), you're free to structure your world however you please. Is your world covered in flying islands, with an unknown, unexplored ocean hidden beneath the clouds? Do it. Is your world a place without magic, imitating the effects of an anti-magic field across the entire surface of the planet, except around these special crystals? Have at ye, as long as gods, artifacts, and Greater Paths still work. Does your world magically stabilize anyone who dies of anything other than old age or coup de grat? There's probably some horrifying implications that might cause, but done.
As long as it obeys the mechanics of the game, the world is your proverbial oyster.
That said, it should be noted that missions you run inside your Domain still need run through the approval process, just to make sure everything remains consistent across the game.

Your Gifts

Your own characters, as extensions of your own will, are gifted with a limited form of immortality once your Domain comes into being. Should they die for any reason other than old age while in your Domain, the character will regenerate somewhere within the Breach ... assuming you let them (something something "my character is not willing to be resurrected").
In a sense, your characters become demigods of your Domain, whether they or the people who live in the world recognize or know it.

Requesting a Domain

To request a domain, take all the above information and head over to blame-a-gan. Give us a short summary of your world and its pantheon, including any relevant post guidelines visiting players should be aware of ("everyone native to this world is a kobold, so don't be surprised if nobody trusts your basic human-lookin' ass", that kind of thing) and tag the post with Lore, Submission, and Domain. Leave a comment under the post with any forum tags you want (you need at least an "OOC" tag and a game area tag, like a continent or major city). Staff may then follow up with additional comments and/or tweaks if necessary, but on approval will create a forum channel for you under Domains.
Do note that you do not have administrative control over the forum (being able to edit post guidelines, change forum tags, etc). If these ever need to change, add the request as a comment to your original submission thread for the Domain and as normal, give staff up to 24 hours to respond before pinging anyone.
By the way, you are free to also submit maps for your Domain. These can be added to your Domain's world anvil page once uploaded!