[[AC:FridgeBrilliance]]
* It took me a while to realize that the password that opens up the exit to the Mechanical Age in ''VideoGame/{{Myst}}'' is actually a representation of everything you had to do to make it there. The C is for the two C's you had to align to get the elevator working, then there's the icon representing the elevator buttons you had to figure out to access the rotation controls, then the third icon is three spikes and a circle, representing the three surrounding islands, two of which have round platforms that show you parts of the password while one has the round platform you put the password into. The last icon is a semicircle which I saw as representing the fact that you have to go back to the entrance where the semicircular gear is.
* The five sounds needed in the Selenitic Age are the sounds of whistling rocks, running water, blowing wind, rumbling lava, and a broken clock. If rocks are taken to represent earth, and lava represents fire, the first four of these are the four classical elements. The clock can be seen as a fifth element of time.
* In an interesting "close the circle" loop, consider the original Myst book that brought you into the Mystverse. Atrus said, "I've tried to speculate where it might have landed, but I must admit such conjecture is futile." In the beginning of Uru, as you're wandering around the hill in New Mexico, you find the remains of the scope that collapsed into the Star Fissure at the end of Riven laying on the ground. Assuming that the book landed anywhere near where the scope did, Atrus's Myst book landed less than a hundred yards from the cleft where he grew up and first learned of the Art of Writing, as described in The Book of Atrus.
* If you wait long enough after the panel goes black in the bad endings where you free the brothers, there's some sound going in the background. The Red Book has some low subterranean rumbling, and the Blue Book has a harsh wind blowing with some crumbling rocks. In Myst 4, you get to see the worlds those books originally linked to, and those same sounds can be heard in a certain location. Spire's is in a corridor between [[spoiler: one of the elevators and the Spider Throne]], and Haven is around the area where the [[spoiler: shipwreck]] is.
* In The Path of the Shell, the old fireplace code only gives you a Relto page. Everyone knows that the way to get the new combination is by overlapping grid patterns throughout the other Ages. But there's another allusion to it in the first game. Flip 10 pages back from page 158 in the pattern book, and you'll find that the new code was right there the whole time.
* [[FridgeLogic Fridge Logic]]: Atrus clearly has access to empty books in K'veer while trapped (hence how he wrote the trap book for Gehn, oh wait, [[RetCon I mean the fake K'veer book that the Stranger somehow convinced Gehn to use]]). He's trapped in K'veer, a mansion in the ancient D'ni caverns, ''directly under'' the Cleft, which is where the fissure ends up and where his book fell. So if I were Atrus, I would have written the "Giant Drill Bit Age" or similar, then used the machinery there to drill my way out of the mansion into the caverns, then to the surface--and oh, look, there just happens to be a fully functional Myst book here, meaning Atrus isn't trapped anymore! Although to be fair, he was probably too busy keeping Riven stable so his wife wouldn't ... wait, what's the worst that could happen? She falls into the fissure? That's even better! Imagine if Atrus had tunneled out to the Cleft and found his Myst book ''and'' his wife waiting for him. Then again, by then she would have been able to collect the page from the vault and free him anyway ... but then she wouldn't find him there because he would already be tunneling out of the caverns, meaning they'd chase each other in circles around Myst and D'ni, eventually find each other, burn the red and blue books, and call it a day. The Moiety meanwhile would have all fallen into New Mexico and assassinated Gehn, unless he was in 233 at the time, in which case he'd be trapped there, which is even better. Of course, then there would be nobody around to link into J'nanin once Saavedro stole the Releeshahn book, unless they had a Moiety man over to visit at the time. But yeah, the Stranger seems pretty extraneous when you think about it.
** The worst thing that could happen if Atrus stopped trying to balance Riven is that Riven could have destabilized badly enough to "unlink" from the Reference Book (which it eventually did), either rendering it unstable enough that it would be unsurvivable or permanently breaking the link, separating Catherine and Atrus forever since no known links between Riven and D'ni existed in Riven or accessible contact Ages. If such a link existed, Gehn could have used it a long time ago to return to D'ni, which would break the plot point that Gehn would use the trap book because he had no other way back to the city, and neither Atrus nor Catherine nor Gehn knew about the Star Fissure link. The fact that Atrus "tried to speculate where it might have landed" when his Myst book fell into the fissure indicates that he doesn't know that the Star Fissure leads to the Cleft or even if a fall into it was survivable, and so he'd have no way to know until after the events of Riven that such a thing was possible (the Stranger having survived the fall when Riven collapsed and then returned), at which point it was moot.
** And as for "Giant Drill Bit Age", that is essentially what Atrus does at the beginning of the Book of D'ni; he Writes Averone with the intent of getting more manpower with which to break out of K'veer and find any more survivors.
* The Selenitic Age is the only one in which Sirrus and Achenar don't have rooms, and at first glance the placement of the red and blue pages appears to be fairly arbitrary; however, it was later echoed in the nature of their respective prisons in ''Revelation''. Achenar's page is in the 'Oasis', an area with trees and running water, and his prison age, Haven, is a lush desert island. Sirrus' page is in the Crystal Forest, and his prison age, Spire, is made entirely out of crystal.
** Not only that, the reason why Sirrus and Achenar didn't keep rooms on Selenitic Age simply because there weren't any people there to dominate, so they didn't care about it.
*** I thought all those bedrooms were simply vacation homes that Atrus built for them when they were growing up, and Selentic had none because the age was unstable to begin with, and aside from the SceneryPorn there was really no reason to stay there long periods at a time.
** Also, the Selenitic crystals where you find Sirrus's page produce eerie musical tones. [[spoiler: Getting crystals to produce sound vibrations is crucial to the Spire Age's main puzzle in ''Revelation''.]]
* The first time you view Sirrus's recorded entry on Achenar's imager, you're puzzled that he's managing to speak to you and remind you to take just one page from wherever the Red Book has him locked away. Later, after you catch on that there's a solitary ''white'' page hidden away also, you realize that [[spoiler: it was a message he'd left Achenar when the brothers were plotting to sabotage Atrus's Myst book, and proof positive they were co-conspirators]].

[[AC:FridgeHorror]]
* That ape head trophy displayed in Achenar's room on the Mechanical Age? Just some animal Achenar hunted once? Well, the inhabitants of the Channelwood Age were said be "monkey-like" in the journal, and Achenar had that chop-you-in-half table.