A database of question-asking mechanisms found in interactive fiction—parser-based, choice-based, and hybrid. Each entry describes what the mechanism is and how it works, with examples. Answers to examples appear in invisible ink (highlight to reveal).
How the player moves through and perceives the game world. IF spaces are not experienced visually but constructed in the mind from text. The mechanisms below govern how that construction happens—what information is given, what is withheld, and how traversal itself becomes a form of understanding.
"You can go north, south, or east." Every room description that lists exits presents a closed set of directional options. In early text adventures, navigation was the primary question asked over and over: where next? The game usually does not say what lies in each direction—only that the direction exists. Choosing is choosing blind, unless you have been there before or the description drops a hint. The question is not just "which direction?" but "what do you remember or infer about each one?"
EXAMPLE: Great Hall THE COLD AIR IS THE ONLY CLUE ABOUT WHAT LIES IN EACH DIRECTION
A vaulted chamber. Passages lead north, east, and down. Cold air rises from below.
> _
A set of rooms with identical or near-identical descriptions where exits do not behave predictably. Going north then south does not return you to where you started. The maze demands external record-keeping—dropping objects to distinguish rooms, drawing maps on paper. The game world becomes adversarial to memory. The classic formulation is Crowther and Woods' "a maze of twisty little passages, all alike." Variations include shifting mazes (connections change over time), one-way mazes (asymmetric links), and mazes solvable only by a non-obvious trick.
EXAMPLE: You are in a maze of twisty little passages, all alike. GOING SOUTH AFTER GOING NORTH DOES NOT RETURN TO THE ORIGINAL ROOM
Exits: north, south, east, west.
> NORTH
You are in a maze of twisty little passages, all alike.
Exits: north, south, east, west.
> SOUTH
You are in a maze of twisty little passages, all alike.
An exit or area that exists but cannot be accessed until a condition is met: an item obtained, a puzzle solved, a flag set. Gating controls pacing by making the world reveal itself in a designed order. The locked door is the most literal version, but gating takes many forms: a guard who won't let you pass, a chasm too wide to jump, a darkness you can't enter without a light source. The mechanism divides the world into accessible and not yet, and the player's job is to convert the latter into the former.
EXAMPLE: > NORTH THE PLAYER MUST FIND THE KEY ELSEWHERE BEFORE THIS EXIT BECOMES AVAILABLE
The iron gate is locked. You need a key.
> _
A room the player has entered but cannot perceive. "It is pitch dark. You are likely to be eaten by a grue." The space exists—the player is in it—but no information is given. Commands may be restricted: you can't examine what you can't see. The mechanism creates a two-phase relationship with space. First visit: blind, dangerous, minimal. Second visit (with lamp): the room unfolds. Darkness weaponizes the difference between being somewhere and knowing where you are.
EXAMPLE: > WEST THE ROOM WAS ALWAYS THERE; ONLY PERCEPTION WAS GATED
Darkness
It is pitch dark. If you proceed you will likely fall into a pit.
> LOOK
You can't see a thing.
> LIGHT LAMP
Wine Cellar
Dusty bottles line the walls. A narrow stair leads up.
The initial description of a room is the game's primary tool for conveying what matters. Every detail included is a signal; every detail omitted is a boundary. Experienced IF players learn to parse room descriptions like evidence: mentioned objects can probably be examined or manipulated; unmentioned features of a room (the ceiling, the floor, the air) probably cannot. The description is simultaneously atmosphere and instruction set. Some games change the room description based on prior events or repeat visits, making the text itself a record of what has changed.
EXAMPLE: Kitchen THE POTS, THE KNIFE, AND THE DOOR ARE INTERACTIVE; THE CEILING, FLOOR, AND WALLS PROBABLY ARE NOT
A cluttered kitchen. Copper pots hang from hooks. A heavy knife rests on the cutting board. The back door is ajar.
An exit that works in only one direction. You jump off a ledge and cannot climb back up. You slide down a chute. A door locks behind you. One-way links violate the default assumption that traversal is reversible, which makes them feel consequential. They impose commitment: once through, you must find another route back (if one exists). In extreme cases, one-way passages are traps that maroon the player in an unwinnable state. More generously, they enforce a sequence—the player must proceed forward.
EXAMPLE: > JUMP THE RETURN PATH IS GONE; THE PLAYER MUST FIND ANOTHER WAY AROUND
You leap across the chasm and land on the far side. The gap is too wide to jump back.
> JUMP
You can't jump that far.
The player enters an object that itself moves through space: a boat, a mine cart, an elevator, a flying carpet. While inside, normal compass navigation may be suspended or transformed. The vehicle becomes an intermediate layer between player and world—you move the vehicle, and the vehicle moves through rooms. Some vehicles are controllable; others follow fixed routes. The mechanism reframes navigation from "which direction?" to "how do I operate this thing?" and often restricts exits to wherever the vehicle can go.
EXAMPLE: > ENTER BOAT THE PLAYER'S MOVEMENT IS NOW GOVERNED BY THE BOAT'S CONSTRAINTS, NOT THE ROOM'S EXITS
You climb into the small rowboat.
> NORTH
The current carries the boat downstream. You pass through a low tunnel and emerge in an underground lake.
Answers to examples are in invisible ink after each question (highlight to reveal)
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