Brandon Leon-Gambetta's Pasión de las Pasiones contains a choice bit of design: roll with the questions; a fit mutation in the phylogeny tracing back to Meg and Vincent Baker's Apocalypse World. It leads me to propose functional design by analogy to computer science, and it might just be the secret sauce of modular old-fashioned adventure gaming.
Nearly all games of Apocalyptic lineage toe the line of Dungeons & Dragons by assigning each character a set of numerical traits (stats, ability modifiers, labels - terms vary). These are then used throughout the common and playbook moves to modify the common 2d6 dice roll. A well read example from Apocalypse World is act under fire (underline mine):
When you do something under fire, or dig in to endure fire, roll+cool.
On a 10+, you do it. On a 7–9, you flinch, hesitate, or stall: the MC can offer you a worse outcome, a hard bargain, or an ugly choice. On a miss, be prepared for the worst.
The implication of this rule is that a character with a high Cool stat is more likely to achieve a desirable outcome and avoid complications when acting under fire, and indeed this is the only contributing factor. This may seem a facile observation, but the reliance on character's numerical traits is an oft unexamined assumption. We are inured to adding a Strength modifier to a class and level game's base attack bonus, or adding a Charisma modifier to an encounter's reaction roll. It is curious that this design was preserved in Apocalypse World, despite the motivation for moves to define the verbs of characters, rather than their adjectives.
Pasión de las Pasiones is different: when you roll with the questions, you roll 2d6 and add +1 for each question you can answer affirmatively (between +0 to +3). Let's consider it's equivalent move to act under fire, act with desperation (underline mine):
When you act with desperation, tell the MC what situation you want to avoid, and roll with the questions:
❥ Are you doing this for love?
❥ Are you doing this for vengeance?
On a hit, you avoid the situation you wanted to avoid. On a 10+, you also manage to hold everything together and avoid further complication. On a 7–9, mark a condition or the MC will give you an unforeseen consequence or added complication.
Each playbook also has a question that is asked for every move they take, such as El Jefe's:
❥ Are you taking control of this situation?
This is fire. Rather than favouring the odds because your character is just generally Cool, we instead see that desperate acts are most likely to pay off if you are driven by love or vengeance (or better, both!) and for El Jefe if they are also taking control of the situation. This opens an entire new axis of move design (apart from triggers and actions, checks, and saves).
Strictly MOSAIC secret sauce
Michael Prescott (who I believe has a background in software engineering) proposed an intriguing design challenge called MOSAIC strict (it does not specify adventure gaming as the intended play culture, but that is the milieu that it was borne from). To summarise the necessary elements that form the acronym:
❥ Modular: Any game text that explicitly claims to be
an entire, complete RPG is not Mosaic Strict.
❥ Optional: Any game text that describes itself
as necessary for play is not Mosaic Strict.
❥ Short: Mosaic Strict game texts are no more than 1500 words.
❥ Attested: Mosaic Strict texts say they are Mosaic Strict.
❥ Independent: Mosaic Strict texts do not refer to the mechanics
or quantified state in any other game text.
❥ Coreless: Mosaic Strict texts assume nothing else is in use beyond free-form play.
This deliberately establishes the absence of any core conversation structure, conflict resolution procedure, dice mechanic, or character traits (beyond those diegetic elements of the shared imagined world). Despite the challenges, there has been a good bit of work in this abstruse field already. For my mind, however, some common design patterns would facilitate both designing and learning these modules. Usually, the only element that anchors them to their game of origin (and would make them unsuitable for MOSAIC strict use) is the reliance on a character's stat.
The rules format of Apocalypse moves has already demonstrated excellent fitness and fecundity in the wilderlands of imagination game design. It is conserved even in the crossbreeding of so-called OSR and PbtA games like World of Dungeons, Freebooters on the Frontier, and Vagabonds of Dyfed. It needn't only be applied to character actions either: non-fictional triggers like start and end of session can provide metagame procedure, and moves can also be referee-facing (rewriting random encounter checks, reaction, or morale rules in this fashion is trivial).
By analogy, these moves are akin to functions in computer programming. If we consider the imagined world to be like a blackboard, it provides the consistent canvas from which these functions draw their inputs and write back to as their outputs. Moves have always fed back their output to the fiction, but traditionally have been unable to take much input apart from their trigger. To roll with the questions fixes this incumbent issue.
A quick aside: these ideas are complementary to what the author of Diegesis aptly termed the concept of the rules funnel, in contrast to consequential narration. It will depend on the selection of moves in play, and the precise wording of each move, how much of the fiction is consequentially carried forward, versus abstracted and elided by the moves.
The popular microgame World of Dungeons by John Harper can be hacked and slashed with this technique to trivially create a load-bearing move for adventure gaming that is MOSAIC strict, but still takes as input all the usual suspects from old-fashioned skill systems (training, tools, teamwork, and time):
When you attempt something risky, sum 2d6 and roll with the questions:
❥ Are you trained for this?
❥ Are you benefiting from an appropriate tool or teamwork?
❥ Are you prepared or have ample time?
A total of 6 or less is a miss; things don’t go well and the risk turns out badly. A total of 7-9 is a partial success; you do it, but there’s some cost, compromise, retribution, harm, etc. A total of 10 or more is a full success; you do it without complications. A total of 12 or more is a critical success; you do it perfectly to some extra benefit or advantage.