When a mortal being capable of dreaming falls asleep, their monadic (fundamental) soul separates from their body and—while maintaining an esoteric tether, and never moving physically—it plummets metaphysically downward, through the Ethereal Plane (which acts as a doorway, or a membrane) and sinks into the Dimension of Dreams.
As the soul arrives, a bubble of sorts is created around it: an infinite—yet wholly individual—demiplane, or pocket dimension, that encapsulates the soul.
This is called a dreamscape.
Each dreamscape is individual, unique, and temporary. Inside the dreamscape, the soul manifests a dream body and inhabits it. And then that dream body, carrying the dreamer’s soul and subconsciousness, has whatever adventures or experiences it has there. Anything is possible. But nothing is real. The people you meet there are not there, they are simply projections of your dreamscape, created by you, for you to interact with.
Sometimes a dreamer becomes aware of the dream and their dream body becomes lucid. This is a powerful state for the dreamer to be in because a lucid dream body has a lot of power inside their own dreamscape. They can change themselves, change their environment, change the other projections—all depending on the strength of their will and the force of their personality.
But this represents a slight deviation from the “normal” course of events.
A non-lucid dreamer wakes as a natural unconscious process whenever the dream is “over” (however that may be defined), but the lucid dreamer must wake themself. They do this either by 1) willing themselves to wake, or 2) by dying inside the dream.
Everyone’s individual dreamscapes float around inside the Dimension of Dreams, and dreamers have their nightly experiences there. Every once in a great while, one person’s dreamscape may briefly brush up against someone else’s, and because the boundaries at the edges of dreamscapes are so porous, a dreamer may pick up elements of someone else’s dream and find them roaming around inside theirs.
You dream what you dream, you wake however you wake, and then the dream ends. The infinite demi-plane your brain created (the dreamscape) ceases to exist. It’s gone forever, along with everything inside of it. Your brain may try an infinite number of times to recreate a certain dream, but all it can do is create a new one that resembles it.
That is the normal course of events. Nobody really knows whether the creation of the dreamscape and the dream body all happens as a supernatural ability inherent to the soul, or if it’s something Desna makes happen (either consciously or unconsciously), but as much as certain scholars love to argue about it, it kind of doesn’t matter in the end. That’s just how dreaming works, and as long as you’re inside this normal structure of the cosmic esoteric cycle, there’s very little danger in it.
When danger can arise, however, is when/if a lucid dreamer can’t manage the act of waking themself up. Perhaps their will isn’t strong enough, or the tie to Desna has frayed or unraveled. In this case, a monadic soul can become trapped. The line between waking and sleeping grows confused, the soul spends more and more and more time in a plane of existence in state of consciousness not truly designed to last forever, and the consequences can be grave. (This is what happened to Chester Bindlay.) There are stories of people waking after such an experience with serious damage to their sanity, people who sleep for months (or even years) before waking… and some who never wake at all.
Now, the Dreamlands is essentially just another dreamscape. It just so happens to be one, however, that is massive, mobile, and exerts almost what one could think of as this huge psychic gravity. And sometimes when a mortal dreamer’s soul sinks through the Ethereal membrane and into the Dimension of Dreams, it finds itself pulled, as if into a black hole, right into this colossal, ongoing dreamscape. And if a normal dreamscape is essentially the temporary hallucination of a single being, the Dreamlands is like a mass hallucination simultaneously shared by hundreds, or thousands, or millions, of people at once.
Just like in a normal dream, it is possible for one’s dream body to be lucid or not there. The vast majority of the time, people are in a normal dream body and have what feels like a normal dream and then just wake up normally. The exception, of course, is that if they dream of seeing the city of Celephaïs, they don’t see a Celephaïs of their own imagination. They see the same exact city that other dreamers were seeing/have seen/are seeing. Not a Celephaïs that ceases to exist the moment they wake, but a Celephaïs they could literally return to.
Nobody knows how the Dreamlands were actually created. Some believe it’s a place created by Desna to allow the sort of wild and interesting dreaming experiences that happen there to actually happen. Some believe (including Valhadis, the author of The Chain of Nights) that it’s actually the dreamscape of a single sleeping mortal of colossal psychic power, and that everyone who goes there is actually sharing in their dream. That’s a scary prospect, however, because that implies the possibility that one day that unknown dreamer wakes up. And if they do, everything (and everyone) in the Dreamlands will cease to exist.
It’s worth noting here that the Plateau of Leng is not a physical location in the Dreamlands. It’s actually a dreamscape inside (technically, one layer below) the dreamscape that is the Dreamlands. A powerful dreamer is currently asleep inside the Dreamlands, dreaming the existence of Leng… and thus it exists.
It is also worth noting here, as well, how Xhamen-Dor interacts with all of this. Once a mortal is linked to him, though Xhamen-Dor isn’t the god of Dreams, he is a god of dreams. So, he doesn’t make dreaming happen (like Desna seems to), but he can circumvent some of the normal courses of events. He has the ability to draw mortal souls into his dreamscape when they sleep (that’s “you dreaming his dreams”), and he has the ability to witness (and partially direct) the personal dreamscapes of an infinite number of mortal dreamers all at once (that’s “him dreaming your dreams”).
But just like the Dreamlands Excursion ritual breaks all the natural links to Desna and carries its casters to the Dimension of Dreams without her care or protection, the same is true of Xhamen-Dor. When you enact that ritual, you are circumventing reality and traveling to the Dimension of Dreams on your own. The ritual breaks ALL divine ties to the dreaming experience. And that includes Xhamen-Dor.
First Reference: Chapter 110
Other Notable References: —