Everything people make builds on what came before. The original edition of Dungeons & Dragons built on miniature wargaming rules as well as other recent attempts to repurpose wargames to explore imaginary fantasy worlds, attempts like Braunstein, Blackmoor, and the Dungeon! boardgame. Since then, there have been countless roleplaying games built off of D&D, both a few official new editions and iterations, and innumerable attempts by professional designers and interested amateurs alike to make their own bespoke version of the game they love, one that plays the way they want it to.
Our adventures too, build on what's come before. If you want to go explore a fantasy dungeon, well, you know what that's supposed to look like. You have examples in mind that show what a dungeon is supposed to be, along with maybe a few others that show you what not to do. The specifics may vary from person to person, but I bet each of us could make a list of the dungeons that inspired us, and I bet there'd be a fair bit of overlap, and also that your inspiration and my inspiration would both hearken back to some of the same, even earlier things. We know what dungeons are supposed to look like, and thus how to draw them correctly. We know what's supposed to go in them, and in what proportions.
(This is true of any form of culture, really. If you're hoping to make a named kind of thing, then the idea of that thing already exists, and what you're making is a variation on that idea. This is fine. There are very few truly new things, and a lot of satisfaction to be found in making your own version of something, done the way you want it. Cultural change caused by iterations within genres isn't precisely the same as biological evolution, but it's not entirely dissimilar either.)
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| a "Nail House" in China - image source |
So, when you're building off of something else, whether one game that you're updating, a pile of games that you're recombining and mashing up, whether it's something that someone else wrote, or just your own earlier versions and drafts, it's possible that things will get left behind. Things that made sense at one time, that maybe still seem to have a place, but that no longer serve their intended purpose, or don't serve any purpose at all.
Collectively, I think of these kinds of things as vestiges of the past. They're elements of a game that are vestigial, analogous to the human appendix or the goosebump response to cold or fear. Recently a couple of bloggers have started identifying and naming specific types of vestiges.
Clayton Notestine from Explorer's Design identifies phantom cogs - game rules that only serve to connect two other mechanics that could more easily be connected directly. Clayton defines phantom cogs as "any rule, mechanic, or procedure in roleplaying games that doesn't relate to the imagined world, its characters, or audience and instead obfuscates or manipulates other rules, mechanics, and procedures." They're "inelegant or 'extra' mechanics that only relate to other cogs."
Two of Clayton's examples are ability scores in D&D 5e and the difficulty scale in Numenera. Both are numbers that are theoretically supposed to be primary, that are supposed to be used to derive other, secondary numbers that will be used in play - the ability modifier and the Difficulty Class, respectively. But in practice, you'll often just know the secondary number you want to use in play and then have to work backwards to reverse engineer the supposedly-original primary number.
Nova from Playful Void identifies forsaken easter eggs - things hidden in a dungeon or other adventure that there's no way for the players to find, because they're not hidden in a way that anyone would guess, and there are no clues that would indicate that they're there. Nova explains that they "do not help the referee better run the module, but they are referee-facing rather than player-facing. They’re easter eggs, because they’re a secret message, and they’re forsaken, because they’re the one so well hidden that they’ll never be found by the kids on the hunt."
Instead of being left behind and getting in the way like phantom cogs do, forsaken easter eggs are left behind without any way to interact with them, because the information that would let you find the hidden thing never made it out of the previous draft (and I think most likely, never made it outside the dungeon designer's head). If you've written and are running your own dungeon, you might remember to include clues in your descriptions that aren't written on the page, but in published adventures, where the person refereeing the dungeon isn't the person who wrote it, forsaken easter eggs are like buried treasure with no X and no map.
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| a "Nail House" in Shanghai - image source |
Can we think of any other types of vestiges? In video games, it's fairly common for glitches, hacking, or player access to the source code to reveal hidden areas of the map that there's no way to reach through normal game play. There aren't many examples of abandoned levels in pencil and paper games though. There's one Choose Your Own Adventure book with an ending that can be found by paging through the book but can't be reached by following any of the narrative pathways, but only one. I suppose you could create an abandoned level within a larger dungeon, by accident, if you made a level or sublevel on your map and then forgot to include any doors, staircases, or other connectors that would let the players reach that area. I'm not aware of any published examples of that sort of thing though.
We can also imagine an opposite counterpart to vestiges, to describe things that used to be present in earlier games, that might still be useful, but are simply no longer present, although I'm not sure what to call them. All the biological equivalents I can find, like blind cave fish losing their eyesight, are called things like "devolution" and "degeneracy," and it kind of seems like eugenicists and other racists care way too much about them. I might use a term like "phantom rules" where the analogy is the phenomenon of a phantom limb, a thing that is no longer present but still felt and missed, but that would sound too much like Clayton's term, and create confusion.
