realMyst Savegame files
When you save a game in realMyst, a file is created: A savegame file. These files contain a wealth of fun and possibly useful information. I got the idea of looking through them from the history of Riven egg hunting, which used such files to keep track of changes triggered by clicking certain spots in the game.
Digging through these files is not for the faint-hearted. Unlike the Riven savegame files, these are massive -- between 1 and 5.5 mb -- and there is no way of searching for changes after clicking a spot or taking a particular action.
Nevertheless, tidbits from a typical file are listed below. (For those who wish to dig through a list of references from a typical savegame on their own, I've put a text file here. There are some problems with it, so pay attention to the note at the top of the file.) Some are just for fun; others may contain clues to the few remaining eggs yet to be discovered. In some cases, I've included conjectures on what those references could mean; in other cases, there is an "official" explanation. This explanation comes from correspondence with Steve Ogden, who kindly responded to an inquiry I sent him covering a few of the references. The list below is in no apparent order.
References to Eggs and Possible Eggs
The Kong egg, no doubt.
Rime gas (note the reference to "eastereggsfx" or easter egg sound effects).
The Cyanegg or Face egg (that was a hard one to figure out). The references in the savegame file are actually numbered from 01 to 32, which accounts for all the pictures in the cyanegg.avi file. This is important, as the references to huevo are also numbered (see below).
This is how we became convinced that the NoDoughnuts egg had to occur in the fireplace rather than somewhere in the Mechanical Age (although my own opinion is that all of those Gear Age and bolt clues were red herrings).
This is a reference to the YourInMySightsNow egg, with the "action" undoubtedly referring to the firing of the gun.
These references are enough to make you salivate. The most intriguing possibility is that there is a full blown egg that includes some or all of a 3d player-mode. And note the last five references. I think that "warp" indicates a locked-in track that you travel when you click certain spots. For example, the sn_island_pit refers to the top of the Rime elevator, where you "warp" to the aurora controls after you click on them. I've fooled around with those controls while carrying the torsk gun (even though it is not visible), but haven't gotten anything.
As explained here and discussed in more detail here, huevo and vika are two avi files with frames that are combined in some way to create a set of images, intended (we think) to be seen in the Rime imager. Like the cyanegg references, the huevo reference "sn_island_study..huevo" is actually a series of references, 01 to 21. This, along with the "enablehuevo" reference, is strong evidence that there is a full blown huevo egg yet to be discovered. Triggering this egg would enable us, in theory, to see all of the huevo images "naturally." The vika references are different, lacking a series of numbered entries. The "vika age" reference, however, does suggest that we may be able to somehow see all the vika images from within the game.
Interesting Rime Age references
It looks like these are references to the age with the snowy islands that you see when you input the crystal combination (and guessing the fifth shape) from Atrus's journal in his Rime nook. That age is also discussed in the Puzzle Age section.
I threw these in here to settle, once and for all, the debate over the name of the water creature in Rime. The proper name is "whalethingy."
The Mechanical Age Skeleton ("Bob")
It's probably just because I'm a complete 3d amateur, but I thought the skeleton you can see through the Mechanical Age telescope was incredible. Here are all the references -- note the detail:
mc_bone_axis, mc_bone_carpus, mc_bone_carpus_left, mc_bone_carpus_right, mc_bone_femur_left, mc_bone_femur_right, mc_bone_head, mc_bone_humerus_left, mc_bone_humerus_right, mc_bone_ilium, mc_bone_rib_cage, mc_bone_scapula, mc_bone_tarsus_left, mc_bone_tarsus_right, mc_bone_tibia_left, mc_bone_tibia_right, mc_bone_ulna_left, mc_bone_ulna_right, mc_bone_vertebra
Miscellaneous other references
When you finally get to D'ni and give Atrus the white page, he leaves and "takes care" of things back on Myst Island. "Atruswashere" probably refers to all the changes that take place on the island as well as in the other ages. For example, if you "cheat" by getting the white page without visiting the other ages, the red and blue pages will disappear from those ages after Atrus returns.
These five references to rodent droppings no doubt show up here. The five names refer to Cyan employees.
I found these three "Og" (Steve Ogden) references and included them just for fun. Here's Og's official explanations:
sn_isl_study..ogsrivenappear "It's a trigger, which makes the image of Riven appear in the Rime Age Viewer. This is the "dream" Katran writes about leaving for Atrus in the viewer."
me_achenar..og'sblackpolyassassinatorlight "This is in response to a series of bugs I kept getting from QA. It seems that someone was just obsessed with ridding the game of what they considered "black polys". Basically, anywhere I tried to put a little contrast into the scenes...a little darkness here or there, this one woman in QA would generate a "texture missing" or "black poly" bug. Eventually, to appease this woman, my bosses forced me to go through the entire game and fix several of these occurences. (there were over 90). In some places, like in this one in Mechanical Age, a few "black polys" were on some of the objects on the floor in Achenar's Toy Room. This was due to the dramatic nature of the lighting in there. But, to appease the Black Poly police, I put a special light in there to "fix" the "problem". So I named it og'sblackpolyassassinatorlight because I was assassinating the black polys in there, with this light."
library..og'snoggintousenbo "Since realMYST began with our friends at SunSoft, there is Japanese all over this thing. Most of the places they used what we call "blockers" (invisible walls and floors to keep the "player model" from falling out of the world) they name them Tousenbo. I'm not sure, but I believe this means "to block the way", or "wall". It's a trigger insurance policy: In the library, if you ran out the door, you would hit this little bump in the floor, and it would act like a ramp, propelling you upward, and your head would pass through the wall above the door. So, I made a little inverted ramp, or Tousenbo, over the door, for your head, or "noggin". In this way, I hoped to keep you from passing through the wall, and sometimes, falling through the world."
Just for fun. Steve Ogden also provided explanations for some of these:
incaseyoufalloffladder "I don't think this is one of mine. I had a tendency to put Og into my trigger names. This one, however, could have been in any one of the ladders in the game. The player kept falling off of things like ladders. So we put in some triggers which would disengage the "climbing" behavior if you fell off the ladder. Otherwise, you'd float, or sometimes, fall through the world. Geez, come to think of it, a lot of what we did was prevent you falling through the world, and provide backup systems in case you did."
cabin_kaidan..notinmystairsyoudont "Kaidan is the Japanese word for Stairs or Stairway, and this one's in the cabin in Stoneship. Although it doesn't have Og in the title, this is one of mine...the water from Stoneship's exterior kept showing up in the stairway there (think about it, the water is one big object, and the stairs actually interpenetrate that...there's no real "boat" to keep the water out...) so I had to set up some triggers to turn off the water down there, and it was more difficult than it needed to be."
toy_veranda..loserpistonforlamecollidesystem "This also isn't one of mine. I think the artist here is obviously expressing some frustration with the collision system, for the reason I already articulated. In this case, we made a piston which would shove you out of the way when the doors opened in Channelwood, or they'd knock you off the walkways and you'd fall through the world."
Let me know of any other fun ones I've missed.