This division can apply to locations on an overland maps, objects within dungeon rooms, and even to details about locations and objects that the players encounter.
|A landmark in Super Metroid|
Closer inspection reveals something, hidden or secret, underneath
Landmark information is automatic and free. Players hear landmark information the first time without asking, and if they ask, they can be reminded of it as freely as they heard it at first. Learning landmark information doesn't take up any fictional time and doesn't pose any risks.
In a hexcrawl, the keyed encounter is a landmark, but so is the type of terrain. In a dungeon, the main contents of the room is free information, but also the shape of the room and its dimensions. You don't have to ask to be told these things - being told them is what defines a context in which you can ask meaningful questions. It's what defines the start of the turn, what sets the stage where the next act of the game will take place. If your adventure includes read-aloud text, that's landmark information.
An ordinary exit door is an example of a landmark. The judge tells the players the door is there during the initial description of the room. Later, if a player asks, the judge can describe the door in detail again, as though the character is glancing across the room, or recalling it from memory.
|Most chozo statues holds a treasure, but to collect, you must risk approaching|
One statue will carry you to safety, another will fight you to the death
Hidden information isn't automatic - players have to ask to learn it. And it often isn't free - there is often some fictional cost that must be paid to learn hidden information. However, unlike secret information, there is no chance of failure. If the players ask the question and pay the cost, they will learn the hidden information.
Landmark information is free because the characters can learn it from a distance, simply by looking at the surface of a thing. Hidden information is more expensive because it's more intimate. To learn it, a character must be close enough to touch the thing, must interact with it directly. Landmark information is received passively. Hidden information is actively obtained.
There are two costs to learning hidden information. The first cost, which is possible but not mandatory, is time. If your game keeps track of time, then it's possible that learning hidden information will require allowing some to pass. A turn passes, a clock moves one tick, wandering monsters are checked for, the encounter dice rolls.
The second cost is risk. What's hidden might not be beneficial, or might include both benefits and harms. What's hidden might be a hazard, an ambush, a trap. Discovering what's hidden doesn't always mean being harmed, but it does always mean making your character vulnerable to harm. There's no way to learn what's hidden without taking that risk.
The contents of every treasure chest are hidden information, every cabinet, every closet, every safe. Everything under or behind or inside is hidden. Seeking out and finding hidden information is one of the main goals of the game. Our characters don't simply look at the most obvious features of each room before moving on to the next. They explore.
A door concealed behind a curtain is an example of something hidden. The curtains themselves are a landmark, but the judge doesn't announce what's behind them. To find the door, a player must ask what's behind the curtains, must place their character at risk to push them aside.
|Samus Aran's x-ray scope reveals secrets, if she makes the choice to use it|
Some walls can be destroyed with the correct weapon ...
Secret information has no guarantees at all. It is the opposite of automatic, and it's always expensive. It's not just that players have to ask for secret information, as they do with hidden; there is also a chance the judge will continue to withhold the information, unlike any previous type. To learn secret information, players must roll the dice and win. That extra risk, not just of injury but of failure, is what makes secret information more costly than hidden.
Whether players can even learn the existence of secret information is something I think judges disagree about. Some judges would say that proving the existence of a secret and revealing the information should be accomplished as a single step - if you can't reveal the information, then you can't know if there even is a secret there to be revealed. Other judges would say that proving there's a secret and learning what the secret is are two separate steps requiring two different skills. Both those approaches seem to agree on one thing though - the existence of a secret is a secret itself.
I would say that the existence of a secret should be hidden information. I would say that players should be able to prove there is a secret by asking a question and taking a risk. Actually learning the secret should require rolling the dice, but discovering that there IS a secret there to be learned should not be a secret unto itself.
One thing that's useful about this hierarchy I've established is that it helps me think about how players should learn information. You discover hidden information by examining landmarks. You learn secrets by examining hidden information.
There is one comfort for players whose judges make the existence of a secret a secret itself. A player can always suspect the existence of secret information, even if their character can't prove it. This is more or less what some judges mean when they talk about "player skill".
A device that causes a bookshelf to rotate out of the way, revealing a doorway when a particular combination of books are tilted at specific angles, is an example of a secret. The bookshelf is a landmark. The existence of the device is hidden, but any character who inspects it closely will notice that the bookshelf is perfectly flush with the wall, and that the floor is scratched and scuffed in a half-circle in front of it. The operation of the device, however, is a secret. It's not enough to spend time trying to activate the device. There is a chance the characters will try but still fail.
|... some floors destroy themselves at the slightest touch|
The most dangerous secrets are the ones you never thought to look for
I think there are two benefits to thinking about information this way. Thinking about the difference between landmarks and hidden information helps write and tell better descriptions. Thinking about the difference between hidden information and secrets helps decide how to resolve player actions.
The difference between landmark information and hidden information isn't just the difference between what you say when players first enter a room and what they have to ask you to find out. It's also the difference between information that is free and information that comes at a cost.
You actually don't have to give a detailed description of everything the characters can see when they first enter a room. In fact, you probably shouldn't. Down that road lies madness, and ten-minute long read-aloud text. It's probably better if your initial description is short and evocative, if it sets the mood and lists the items available to investigate, and then gets out of the way. That doesn't mean all the other information is hidden. For many items on that list, your additional description should be free, and should be as detailed as the player would like. But it does mean that some information is hidden, and you should know which information is free, and which information takes time or involves risk to learn.
It also helps to think about those occasions when information shouldn't be free. When a character is unfamiliar with a work of technology or magic, they should get a description that makes what's familiar to the player strange to the character. When it's dark, perhaps all that characters can learn for free is the shape and size of objects, perhaps under those conditions more information should be hidden and risky. Total darkness is boring. But instead, think of those moments in children's books about not being afraid of the dark, the moments when you realize the "intruder" is just a hat atop a coatrack, or the "monster" is just a pile of clothes in a chair. Those moments happen all the time in fiction, and hardly ever in games. If applied to more interesting objects than coatracks and laundry, they might add a certain feeling of wonder and mystery to experience of exploring in the dark. Total darkness is a total lack of information. Not everything should be hidden. But having some information require extra effort to collect makes that information stand out. Its very difficulty highlights it, and makes it dear.
The difference between hidden information and secret information is that hidden information only requires getting close and only requires that the character spend time on the task. Secret information requires something more, something extra. Ideally, it requires applying a skill that can't - or can't easily - be modeled by player description. In my example of the secret door earlier, if it was just one tilted book that activated the device instead of a combination, it would probably only be a hidden door. All that takes is time, and there's no chance of failure. To guess a combination though, takes too much time, more time than the characters have, and there's plenty of opportunity to guess wrong. So it makes sense to roll the dice.
If all a search requires is time, and the characters have enough time, then what they're searching for is simply hidden, and they can find it without needing to roll the dice. Checking all the burial niches in a funerary crypt where the dead are interred as though in a vault of unlocked safety deposit boxes, digging up a grave, breaking down a false wall or a bricked-over doorway: these all take time - and sometimes make noise - but they require no particular skill, involve no particular risk of making a mistake or overlooking something.
Something can become secret simply because there's not enough time to find it. A methodical all-day search might be certain to turn up what you're looking for - but to uncover it in a single, 10 minute exploration turn requires luck or insight or skill. It requires rolling the dice. For there to be not enough time there has to be some kind of time pressure, some kind of countdown or deadline, either narrative or mechanical, some kind of reason the characters can't just spend all day. Remember, for the players, that search only takes as long as they need to say they agree to it.
There can also be not enough time because of the skill required to make the search. Not all problems have easy solutions. Trying to solve them just by spending time might require, not hours, but years, centuries. Knowing how to solve a problem like that quickly is a skill. It's special knowledge that not everyone - not every character - possesses. And even if a character has the right skill, there's still a chance that they'll fail. So roll the dice. Roll the dice, because the alternative is to make the players try to act out their characters' searches. Roll the dice because while the characters might have all day, the players don't, and their time, your time, is worth more than trying to devise and explain the correct search algorithm.
Again, not everything that isn't a landmark should be a secret. Some things can simply be hidden. Having to explicitly request to look closer is already a barrier to discovery. The additional barrier of a dice roll is appropriate in some situations, but not every situation.. But before rolling the dice, decide if the information is secret or just hidden - decide what it would mean for the characters to be able to fail in their search. If you don't think they even could fail, then it's not really a secret, and you don't need to roll the dice.
Some games include conditional information that is halfway between hidden and secret. Like secret information, it can't simply be found by every character who looks. But under the right conditions, it can be found, with no chance of failure, like hidden information. Skills in Trail of Cthulhu and its sister games work like that. If you have the right skill and you search for a clue, you will find it. But if you don't have the skill, you simply can't find it. Equipment in a lot of video games works this way. In A Link to the Past, if Link has the right magic gloves, he can lift boulders to clear a path, but without them, the path remains blocked. In Super Metroid, Samus needs specific ammunition to shoot down specific doors; without the right ammo, the doors remain closed.
A final note is that some games have only secrets, with no hidden information that can be learned without making a skill test. In the earliest dungeons, you can't even open a door without passing a skill test. I think how difficult it is to gain information should be based on its importance to the game.
If the players have to know some information, it should be landmark. This is true of all the visual description needed to create a shared image of the game world in everyone's imagination.
If information is really important, it should probably be landmark or hidden. No player wants their judge to "fudge" and lie about the result of a dice roll, or to "railroad" and seize control of the characters to make them do something ... but no one wants to cancel their expedition and spend the rest of the session hastily putting together a back-up delve just because they couldn't find the one secret door that revealed the rest of the dungeon either.
Information can safely be made secret under one of two conditions. The first is if that information is truly optional. It might be very nice for the players to find it, but the game won't come to a complete halt if they can't. The second condition is if there are a variety of ways to learn the information. If there are at least three ways to learn a piece of information, and the characters botch every attempt, then perhaps it's okay to let them fail. No one wants the entire group's game to end for the night because of one bad dice roll, but three bad dice rolls, accompanied by three rounds of planning and three narrative descriptions of the attempt mean that failure hasn't stopped the game - watching the characters fail has become the game, at least for this night and this secret.