This article is mostly an attempt at naming and cataloguing some recurring design ideas from Fallen London, which are definitely relevant to anyone building a game largely out of storylets—but also probably interesting to look at in the context of games with storylet-narrative systems, such as strategy games with Paradox-style event systems or many other kinds of narrative games.

Storylet systems in games vary wildly in their role; for some games, like Fallen London, the storylet system is almost the entire game. Other games use a storylet system as one component of a broader narrative design; or as the main narrative component of a game that's not story-driven all the time. So the applicability of these patterns will vary, but they are all generally relevant at least to either the maximalist use case of a storylet-driven game like Fallen London, or the lighter common use case of event systems such as the one found in Civilization VII.

This is also, obviously, not a comprehensive description of every possible way you can arrange storylets together—really their point is that they go together in an infinite number of ways. But these are some commonly-seen structures.

The Chain

The chain is a mostly-linear series of storylets meant to be played in order. Some storylet systems (like the StoryNexus engine that underlies Fallen London) have an explicit affordance for "linking" storylets together in order, though that isn't strictly necessary. A very common way to implement a chain is to simply have a quality^[1] that monotonically increases as the player progresses through the chain, unlocking each storylet in turn.

A chain can have branching, player choices or other conditions affecting which storylets will be seen as part of the chain. But the defining characteristic is that they move towards an ending. Your typical Fallen London monthly story is a chain, as is your typical event chain in Europa Universalis IV. They can be almost like little islands of structured branching narrative nestled within a broader storylet system.

The Wheel

A wheel^[2] is really just a chain with the ends tied together; it's a sequence of storylets meant to be played sequentially, but with a reset at the end that makes the start available again—so it can be played over and over. Wheels are the basic structure for implementing recurring or repeatable events in a storylet system.

In Fallen London, repeatable activities are usually designed as wheels, though they sometimes have little curlicues; it's common, for example, for wheels in Fallen London to involve playing the same storylet repeatedly multiple times before advancing, a pattern that's a bit more like a Clock. Another example of a wheel are the various activities in Crusader Kings 3, like going on a hunt or hosting a feast; they play out as a series of storylets with a distinct beginning, middle and end: guests arrive, carouse, depart in order. But which storylets play out can vary, and of course when they play out they will bind to different characters and situations in your particular moment in the game; and they're designed to be played through many times in the same game.

The Clock

The clock is a single storylet (or cluster of storylets) that recurs over time, incrementing a quality each time you go through them; eventually, that quality hits a certain threshold, which advances the clock. Think of the second hand of an actual clock doing a full revolution and then the minute hand ticking when it does.

"Advancing the clock" typically means incrementing a second quality (the minute hand, in our analogy). As that quality changes, it would then also change the contents of the recurring storylet, reflecting that the situation has shifted.

Clocks can be nested multiple times; you could have a second, minute, and hour hand. But because of the "gear ratio" involved, progress in the higher layers quickly becomes exceptionally slow. In Fallen London, clocks are typically used as an organizing principle for stories the player is meant to see very gradually unfold through the card deck.

The feeling is that of a slow boil, or a gradually developing situation. For example, a clock might depict a slow burn romance, with each "hour" being a collection of storylets about phases in the relationship—meet-cute, flirtation, dating, etc—which can show up in different orders and under different conditions, until you see enough of them that the relationship moves on to the next phase. A common pattern in clocks is having storylets that sit on these "hour hand advancing" moment and act as the stitches between each phase—chimes, if you want to call them that.

The clock pattern can also be used to build repeatable or recurring content, which I suppose makes those clocks wheels.

The Hourglass

Many storylets scattered throughout the game all increment one quality, usually as a side effect. When that quality hits a threshold, something happens. This is your basic "fill a meter" mechanic found in many games, as applied to storylets.

One example is the "Someone is Coming" quality in Fallen London, which increments naturally on many cards in the London deck; when it fills up, the player will see a storylet that gives them a reward. But the "menace" design that Fallen London uses, where instead of having a decreasing set of hit points you have an increasing "wounds" value, is also an hourglass. Another example is stress in Crusader Kings III; acting against your natural proclivities (being industrious while playing a lazy character, say) increments stress, and when stress maxes out you suffer a mental break.

The Gravity Well

A set of storylets that play out in sequence, possibly with branching; but once finished, they leave behind a repeatable storylet (or small cluster of storylets) that takes their place. Like falling linearly towards a planet and then being caught in its gravity and falling into an orbit.

Gravity wells are actually quite common, because they're a feature of many games where a storylet system (Or a much simpler, storylet-like setup) is used to fill in the content for something the player can choose to do. The bottom of the well is the content that fills in if the player exhausts the linear content that comes before it. In Persona games, for example, hanging out with your friends functions this way; there's specific scenes and conversations that can play out when you hang out with a party member. But if you exhaust them, the game will still let you do it—it'll just give you a much shorter generic scene instead.

In Fallen London, several of the "mountain qualities" that represent understanding the setting's deep mysteries (like "Approaching the Gates of the Garden", which deals with the question of immortality) are progressed through a slow-moving clock which eventually ends in a gravity well.

Gravity wells can be implemented purely linearly—once you exhaust a line of content, you'll always see the "bottom" if you look again—or they can be a more dynamic feature of a storylet system, where a new storylet in that line of content might unlock later on and displace the fallback storylet once again. But they are the simplest way of answering the problem of a player trying to do the same thing over and over and exhausting the material written for it.

Often but not always, the "bottom" of a gravity well is written or designed to signal that the player has exhausted this vein and should go do something else, without immediately denying their choice.