So a rewrite to a Descriptive Book that makes changes that are too drastic will make it link to a completely different Age. That's fine. But what's the big deal with severing that book's link with the previous Age permanently when you can just write another copy of the book without the changes and create a new link to it?
That's the thing. They've tried that, but it never links to exactly the same age. See, the way I understand linking is that it takes the parameters of what you write, and links to an age like that. For example, if you made an age that was "A green sky, and an ocean", it would create an age with a green sky and ocean. However, what colour is the ocean? Are there other land masses? Every time you re-wrote that sentence, it would link to a different age. Even if you made the most specific age, it could simple move an underground boulder a few inches to the right. You specify that boulder's position? Wonderful, the age makes another. You specify the number of boulders the age has? It quickly deteriorates into an unstable age because it can't support the weight of it's soil. Writing is a game you can't win.
What's more only a Linking Book will lead back to the same age it was written for. Any Descriptive Books made after will link to somewhere else. Interestingly enough Gehn's Descriptive Book only changed it's link when Ghen put the delete symbol which might very well have erased some of the book's history. Changes can only be made concerning things in the present. The Great Tree of Riven was cut down so in order to change Riven the tree's being reduced to a stump must be acknowledged by the writing.
In the library on Myst Island, most of the books have been burned—Atrus forewarns you of this before you first arrive. But why have they then been carefully put back on the book shelves alongside the unburned books?
Two possible explanations: Either the books were burned while on the shelves so that the fire didn't reach all of them, or Atrus put the burned books back onto the shelves himself along with the undamaged journals.
Or Atrus's sons put them back on the shelves, all in their proper places, out of habit after burning them. That could even be why Atrus originally came to suspect it was one of them: an intruder wouldn't have known which order to put them back in.
Actually, it never stated whether there was a time in-between the burning and Atrus's imprisonment. Chances are, Sirrus and Achenar burned the books, then went off to do a bunch of raids (With books they personally salvaged for themselves) while Atrus put them back on the shelf mentally reminding himself to repair them, (Which he explained he attempted many times but failed, in his journal in Exile) despite he had his suspicions, he didn't know for certain who exactly burned them, which is why he laid the red and blue trap books if the vandals ever came back.
How does communicating through Linking Books work? Particularly though intact links like through the D'ni Linking Book on Myst? Does a window pop up in thin air inside Atrus' chamber?
Why not? The link to D'ni puts you right in the middle of the chamber; maybe opening the book opens a two-way window. It would make sense for the D'ni to figure out how to do that. It's possible that Atrus's secret D'ni book was made especially with that ability in mind.
Perhaps Atrus's desk incorporates a less-gaudy version of the image screens seen in Uru.
The officially given reason (sorry I don't have a link to where, at the moment; it was in an interview with a gaming magazine and I can't remember which one) for both Atrus and his boys communicating through a linking book is that they didn't, but instead that the Stranger read through their journals and figured out what happened, and was just depicted the way it was in-game because it was easier.
In Myst, we clearly see Atrus jump into the Star Fissure and Panic Link to Myst, kicking off his narration and the opening credits. However, this happens at the end of The Book of Atrus - part of Atrus' plan to Portal Slam Gehn into Riven. A few years later, Sirrus and Achenar are born, and when they grow up, they help Atrus with Rime, visit all his Ages, go through the Philosophy of the Art course on J'nanin, and then go on their rampage. Atrus' original Linking book to Myst, meanwhile, is still sitting in the New Mexico desert. My question is this - Why was it still intact, let alone legible enough to link to Myst Island, after the 30 years, give or take, it took for Sirrus and Achenar to grow up, start their destructive spree, then get trapped in Spire and Haven?
There are parts of Uru (and now Myst Online) where time is out of sync between two adjacent locations (Er'cana's well is a good example) so the idea that something falling through the Star Fissure could arrive on Earth at a much later time isn't beyond belief.
Assuming it's not lying at the bottom of a gulley to get washed away in a flash flood, a desert is a pretty good spot for a closed, thick-covered book to last a long time. Its cover does look a bit worse for wear when it's found.
We can't actually be sure that the book did land in the New Mexico desert. The Star Fissure dumping the viewing device, the bits of floor, and the dead wahrk in that spot may have been a one-time coincidence, or a side effect of all the editing Atrus did to try to stabilize Riven.
However, the Fissure seen in Relto at the end of URU sends the player to the same general spot where the debris from Riven went.
In any of the first three games, we never learn the answer to the obvious question: who are you? Who is "The Stranger?" Where does The Stanger come from? It is entirely likely that Atrus created (or wrote) the player character into existence for the sole purpose of helping him... All well and good until you realize Atrus just keeps leaving The Stranger stranded in various places at the end of the games and does not seem concerned by this at all. Thanks a bunch! There's no transportation, and no food. Although, that could be because Atrus wrote The Stranger not to have to eat to stay alive, something that's entirely possible based on further information received in the novels. And yet even though Atrus seems nice toward you, he's also somewhat dismissive, in the same way a scientist would dismiss a specimen. Hmm, bit of a god-complex much, Atrus? Not as bad as old, psycho Gehn, but still...
The name of the MMO, URU (that is, "You Are You"), answers the question in general terms, although there's speculation as to exactly who Atrus's friend is since that person lived long before the time setting of URU, and there's at least one argument that the Stranger was Dr. Sharper. In the novels and the later games, it's established that the Star Fissure leads to a location in the New Mexico desert on Earth, and furthermore D'ni is an underground cavern also on Earth. Therefore, the Stranger is a regular human, likely American, and not Atrus's creation. At the end of Myst, you're left to wander among the original Ages of that game, all of which contain reasonable access to food and water (and a clear return path to Atrus). At the end of the second game, you drop back into the Star Fissure, ending up back in New Mexico (which is "back where you came from" and from which you could presumably go to your home), and the events of Exile see you visiting your friend Atrus at his house in Tomanha and ending up back in his house when you're done. Since he treats you as an old friend in Exile and you're visiting his home, it can be assumed that you still had access to the original Myst book at the end of Riven (the same one you used to get to Myst in the first place) and you maintained contact with Atrus and Catherine after you met them (which would lead them to offer you access to Tomanha for Exile and later, Revelation).
If Achenar had to break the glass dome in the old Memory Chamber to put the lifestone inside, why didn't he put on one of the breathing kits in the entry shaft first? He wouldn't have died if he used one!
Are the Red and Blue Books in Revelation the original Descriptive Books for those Ages?
Why did Sirrus and Achenar burn all the books? What did they gain from that?
Why did Atrus make special holding areas for those for Ages, since I assumed he made them specifically for those Ages since they match up thematically?
How could Sirrus and Achenar know where the location of the last two pages were, but not know what the Prison books did?