The Artifacts you're trying to collect are held by the Solar Priests, a giant faction that has its tendrils wrapped around anything important in the world. The other factions have been trying to challenge its hegemony for hundreds of years, but the economy is way too reliant on Sunstones, and Scrying magic has made it impossible for factions to grow in any meaningful way.
You play as the Lunar Priest -- there are actually a bunch of these but they're underground and basically waiting for the Artifacts to fall under their control before they emerge. Your faction, the Lunar Priests, want to seize control over the world and return it to individualized magic and magico-oligarch type power structures. They can't do this while the Solar Priests are in charge.
A while back, a few of them emerged to spread legends of a Lunar Priest who would allow the other factions to grow. They're therefore very welcoming when you reveal yourself.
Scrying makes expansion basically impossible -- the Solar Priests have kept the factions at each other's throats and they all have the ability to Scry to see where expansions will happen so they can counter them effectively. It's in the interests of the Solar Priests to have a functional economy so that taxes of products made can be funneled into appeasing the Sun Archon to keep their magical power and hegemony intact. As a result of this, they carefully manipulate things so basic operations aren't permanently damaged by Scrying. They're maintaining a kind of fragile balance.
The world stricture is therefore highly dystopian -- the various Guilds have to work their workers almost to death to keep up production and keep their power intact. Solar Priests have ousted leaders of Guilds that aren't up to par on a number of occasions. Occasionally there are worker revolts that get co-opted by the Solar Priests and become the new powers of an operation. Being part of one of those is basically the only social ladder available, but want-to-be revolutionaries have to be very careful or the guilds will crack down on them.
The Seam is some kind of large-scale Onyx/Amethyst technology that is a permanent portal between disparate regions. How it works exactly is a closely-kept secret but there are some prevailing theories:
Portals do definitely mask the area of the space where they open, so large portals could completely cover a border. Rapid switching of Portal locations between the three borders would maintain the illusion of there being a permanent Portal in place.
The kind of energy required for something like this would be astronomical, but it's well-known that Solar Priests have Solar Magic granted by the Sun Deity and while personal magic isn't well-understood, the energy outputs are potentially orders of magnitudes higher than sunstones.
It's even possible that the Portals here are controlled by personal magic directly rather than piggybacking off Amethyst and Onyx, but large Amethyst/Onyx complexes around the Solar Stair (way more than what's needed for the Stair itself) refutes this idea. It's more likely that the complexes are providing the magical effects and are being powered by personal Solar Magic. The size of the Onyx at these stations does sort of fit into the idea of a very very large space that could completely mask the borders.
As a Lunar Priest, you do have access to some personal magic. Personal magic isn't well understood and only the Solar Priests seem to be capable of it otherwise because of boons granted by the Solar Deity.
Chief of these is the ability to achieve a Wraith form -- Wraiths can see the world but only very minutely interact with it. They appear a bit like dim shadows and things pass through them easily. Wraiths can pass through walls and otherwise remain unseen. As personal magic this can't be removed from you so you're completely untouchable by anyone whatsoever -- this is one of the things spread in the Legend of the Lunar Priest so suddenly becoming invisible is a good way of confirming who you are and Guilds sort of know to just let you walk around freely since they cant do anything about it if you go Wraith.
Wraithed Onyx -- you have an Onyx that allows you to do Courier type stuff, and its world is perpetually wraithed so its contents can't be scryed.
Lunar Scrying -- you have the ability to tell who people are or what towns are like without talking to anyone. This ties heavily into the gameplay. Basically you're tapping into people's subconsciouses.
Lunarisma -- if people trust you to some degree they trust you absolutely. This is how you're able to manipulate Guilds once you gain enough Morale or Reputation. It's a passive effect. The Legend of the Lunar Priest in combination with this also softens people's inhibitions to trust complete strangers so you can pick up Quests quite easily.
These abilities don't work well where Solar Priests congregate. They can't explicitly hold you hostage but they can definitely disallow you from moving through their passageways unchecked. Additionally, Lunarisma doesn't work on people who are Solar-aligned, but thankfully that just matches people who are otherwise mostly happy with their lot in life, so it wouldn't affect quests or anything.
You also can't get a read on people who are Solar-aligned, much less explicit Solar Priests.
Instead of being celestial bodies, the sun and moon are massive magical constructions of unknown origin. It's believed that they were created by a precursor civilization to light an otherwise dark world, but not much is known.
Their cycles can be manipulated somehow, probably via some form of collective personal magic. The Delvelands has 14 hours of moonlit night and 10 hours of sunlit day. The other three main areas have 16 hours of day and 8 hours of twilight. The Seam/Skylands are perpetually daytime.
As magical holographic entities this doesn't have to make a whole lot of sense -- moving from one area to another might radically change the position of the sun, but the sun isn't an actual object in an actual location.
There are six Artifacts of unfathomable power that control the minutiae of natural forces in the world. These were very definitely created at one point by a precursor personal magic civilization:
The Parchstone -- located in the Powdersands, this artifact makes the Bone Desert arid at a level beyond what the lack of clouds does. It skeletonizes newly formed creatures so nothing can live here, allows skeletons to be reanimated, turns materials to sand and creates the influx of wind that creates sandstorms. It's believed that this artifact can be manipulated for different effects but so far nothing has been discovered. Unlike other Artifacts there isn't ancient Jade that has that information stored, there are instead flecks of Jade and powdered Jade that lie on the floor.
Attempts at finding microscopic information in them have been fruitless, so while people here continuously search bigger pieces of Jade at a snail's pace, the bulk of the Jade is just left here. It's believed that the Parchstone itself caused this degradation -- indeed, moving Jade here will cause it to deteriorate over time, the same way stone turns to sandstone over the course of decades. Or how people age more quickly here.
Fertility Pylon -- this inverse pyramid artifact appears as a painfully bright emerald that emanates Wood energy in all directions. It's located at the exact center of the Groveheart, which is itself the exact center of the Valley of the Grove. The entire region and its layout is sort of built around the Fertility Pylon instead of the reverse. It also emanates a more chaotic energy that makes the wilds mutate over time, producing varied potion ingredients. Unlike the other Artifacts, the methods of controlling this one are very much understood, which has led to the Valley of the Grove being *perfectly* equipped for agriculture -- new farms can simply request for more Wood or Chaos energy to be sent their way. While chaos in the wilds can be controlled, chaos as a whole is poorly understood.
Aquatic Contraption -- An ornate machine studded with various otherworldly charged jewels and precious metals, held together by magically hardened Ancient Oak wood. This is located at the head of one of the waterfalls and controls the flow of water within Tidefall. More ornate pipes flow out from the bottom in various directions and run very deep. This artifact is actually in use to shift the flow of water and oceanic currents in accordance with rain cycles which are less controllable than the Solar Priests would like.
However it apparently has much more powerful uses, like changing the position of rivers and seeding clouds directly whose functional knowledge have unfortunately been lost over time. There are ancient Jade tablets surrounding it that contain detailed instructions that don't make sense, and there's a bounty on understanding what exactly they mean, but no one's come close because they largely require personal magic.
Lunar Conduit -- Located deep within the Delvelands and at the same level where the Lunar Priests secretly dwell (but definitely not near them) lies this artifact. This artifact captures Lunar energy and transfers it to jewels, granting them magical power. Same deal with precious metals and energy transfer along them. It can also cause the formation of Jewels from precursor minerals, though like the above Artifact, the understanding about how to achieve this has been lost and the Jade surrounding it isn't helpful.
Xanthite Lion -- the only known Xanthite jewel in existence, small enough for you to pick up in two hands and carved into an ornate and highly detailed shape of a lion, the main avatar of the Solar Deity. The Xanthite lion moves around Seam Stations randomly, lingering at one for sometimes days at a time or jumping between them every second or occasionally appearing vaguely transparent as it occupies several spaces simultaneously. It can even be picked up and examined, though it will teleport again eventually.
Various Ancient Jade does make mention of other Xanthite being in existence, but no other Xanthite has ever been found. It's theorized that the Lunar Conduit would be able to construct it from sulfur, but no one knows how to operate it.
It definitely has something to do with how the Seam works, but how it's used is a closely held secret by the Solar Priests. Some pre-executed deconverts have hinted that it focuses sacrifices to the Solar Deity into a usable form.
It's the only artifact that's freely accessible by the general public -- people can actually pick it up if it's present and feel it, though it will definitely teleport again. Removing it from the chamber is possible, doesn't stop the teleportation effect, but is nonetheless a crime punishable by execution. Granted Solar Priest guards will usually stop you from doing this.
The Solar Priests have some understanding of the cycles and transmit information about where it's likely to be at certain times to aid in pilgrimages -- it is unfortunately quite random so this isn't always accurate. They're better at predicting Simultaneity, where it exists in multiple locations at once, though granted it's some kind of wraithfomed and can only be vaguely seen during those times, not interacted with.
Skywhale Statue -- at the handcrafted Floating City above the Delvelands (the true center of the world) lies a multi-story tall ornate statue of a whale, with gleaming golden eyes that light the entire chamber perpetually. This artifact is the best understood -- it determines where Skywhales appear, the regions where clouds first form, the areas of Skyland islands and settlements where the most Solar energy is pooled, and how cold icy regions up here are. Unfortunately its utility isn't particularly precise nor powerful, or if it is, that isn't well understood. It's operated with Solar personal magic, which the Solar Priests have an abundance of, so they're able to manipulate it to their whims.
Starting out, the Artifacts are tightly controlled by the Solar Priests at various Solar buildings. Out of all of them, the Xanthite Lion is the easiest to control as you only need to loosen the power of one of the Seam stations and then wait for it to appear there.
Meanwhile, the Skywhale Statue is the hardest because of the absolute hegemony of the Solar Priests in the region.
The overall goal of the game is gaining control over all six, which will allow the Lunar Priests to emerge from their city and take over the world. This requires a lot of gameplay to achieve.
People that belong to Guilds will also live there -- in shared communal spaces if they're low-level and more dedicated rooms or even whole apartments if they're higher up in the hierarchy.
As such, none of the towns in the world have residency areas. Guilds and homes are the same thing, with Guildless living in Guildless Towers or outside towns in the world in general.