Introduction (GAP)

: A Guide to the Astral Plane Page
"I've been a planewalker for a few years now, Tarsheva," Felliz explained. While not terribly interested, Tarsheva motioned for him to go on. 
"Well, I've traveled through a number of gates and portals, and been to a bunch of the planes. I've even used an astral conduit or two. But I've never really been to the Astral Plane to speak of." Felliz's normally confident bearing was wrinkled with feelings it was unaccustomed to — conscience, guilt, and possibly humility.
"Uh huh."
"Now, well... I have to go there. The githyanki killed a friend of mine. Sliced her silver cord while she was using the astral spell." He looked about the tiny tavern to check if anyone was listening in. No one was. Most folks in Sigil had better things to do. "She was a prime, and she was coming to see me, out here. Now... I've got to avenge her."
Tarsheva perked up. "Vengeance doesn't do anything but add names to the dead-book. And yours might be one of them."
"Look, I don't care about your condescending concern. I just want your help. I know you know the chant about the githyanki and the Astral, and I want you to lann me."
He glared at her with sullen eyes. Just for a moment, she met his gaze. "Fine. What do you want to know?"
"The githyanki. Tell me more about them. I'm met up with some githzerai, but I've heard the githyanki are different in a few —"
"Very different," Tarsheva interrupted, "but they're not your first, or even your main, concern if you're going to the Astral Plane. By the gods, they're not even natives. Just settlers who called kip there years ago. No, my friend, you've got to learn about how the plane works first."
"I'm listening."
"Ever been to a play?" Tarsheva asked, lifting her cup to her mouth.
"Sure. I've even been in a few. I did some time with a group of traveling actors in Ysgard. We once —"
"Then you can tumble to what backstage means."
"Of course."
Tarsheva pushed her long brown hair away from her face. The scar revealed near her temple served to punctuate her words — an effect she was well aware of and used when making important, but complicated points. "It's not entirely inaccurate to think of the Astral Plane as the backstage of the multiverse."
"Huh?" Felliz said, dropping all pretense of erudition.
"The multiverse is the stage. It's where things happen. It's what folks are supposed to see. The Astral is in the background. It's not something anyone was ever supposed to see. No one was ever supposed to go there. It isn't a there at all. No space, no time, nothing."
"Wait a minute. Back up. The Astral Plane isn't part of the multiverse?"
"Not really. It's the place in between."
"In between what?"
"Everything."
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A Guide to the Astral Plane is a PLANESCAPE™ sourcebook that describes the Silver Void. Home to creatures as varied as the evil race known as the githyanki and the enigmatic, spiritual astral searchers, the Astral Plane has always retained an important place in the AD&D® game. Rather than being just a simple interplanar highway system, however, unique features and strange wonders which can provide limitless and varied adventures fill the Astral Plane.
The Astral Plane holds a unique place in the multiverse. A place solely of the mind, everything there is a construct of the mind, composed only of mental energy. Traveling through this plane changes a cutter, maybe forever.
Terrifying foes, great dangers, and fantastic treasures can be found in this mental realm. The githyanki, an ancient race of magical and mental power, remain the most infamous inhabitants, and rightfully so. No wise blood travels onto the Astral without being prepared for an encounter with these enigmatic creatures, and while they are best avoided, do they possess secrets that could send a well-lanned cutter to the dead-book?
Only a fool would ignore the other threats present on the Astral: horrible creatures such as the astral dreadnought or the terrifying mental storms known as psychic winds. Nevertheless, the dangers are worth the chance to explore the decaying, rocklike forms of the floating dead gods, or to find interesting realms such as the Swallowed City, the Living Sea, or the prison known as Pitiless.
==Reading Between the Lines==
As a canny basher reads through A Guide to the Astral Plane, he'll keep a few things in mind. Terms and concepts like space, distance, time, movement, body, and even plane itself are relative to this strange mental realm — they exist only as perceptions, not as reality. This means that although a body'll find references to distances or measurements (for example) in this work, on the Astral Plane there is no such thing. Even the term "Astral Plane" is a technical misnomer. The first chapter called "The Spaces Between: Astral Space and Time" will attempt to explain all this — but a body should try to remember it while reading all the rest as well.
For ease of understanding — for terrestrial beings have difficulty in comprehending a truly non-terrestrial setting - sometimes incorrect or inappropriate terms such as "up" and "down" are used to describe the Astral Plane. A canny reader will pick up on these references and recognize them for what they are.