Angular Deviation and the Impact of Rules
The Axis
Imagine the flow of play as a physical path. We travel along the line that is our play experience, both narratively (the story we tell) and ludically (the mechanics we use). The direction we travel along this imagined line is called the Play Axis (or, just Axis). Generating a Play Axis is about the current expectations:
Because we are playing Mothership (Tuesday Knight Games, 2024), we expect to have to make panic rolls (ludic expectation).
Because we are playing Good Society (Storybrewers, 2018), we expect the new arrival to town to be a marriageable prospect (narrative expectation).
Because we are playing D&D (WotC, 2014/24), we expect to fight these Giant Wolves using our attacks and spells ludonarrative expectation).
Through their design and context, the game's structures communicate an expected use case (Affordances[1]). This projected expectation is the Axis; it’s “where the game is going if we keep saying the obvious next things.”
[1] Affordances describe the relationship between the properties of an object and the capabilities of an object, and how they interact through the players engagement with them. In this case, an affordance is a piece of design that communicates some form of context-driven play. For example, by using hit points, D&D creates granular combat. Hit Points “afford” granular, turn-by-turn, mixed-stakes, action enomy-driven interactions. (Design of Everyday Things, Don Norman, 2002)
An Axis provides a sense of momentum (playing as expected provides very little friction), but reduces novelty (every next thing is just the most obvious next thing, there’s no freshness). However, good games don’t continuously pursue momentum. Instead, you need pacing[2] to keep players engaged. So, to reduce momentum and increase novelty, you need Deviation.
[2] I’m confident in asserting “good games need to be paced” as self-evident in a piece this deep. If one wishes, I recommend The Art of Game Design (Jesse Schell, 2008). Chapter 16 is about Interest Curves or a review of the concept of Flow Curves in player interaction.
Deviation
If we have constructed this idea of a Play Axis as the directional vector of momentum or the untouched direction of play (again, ludically or narratively), then we can image a world in which that line veers off the path. This is Deviation, a change in the direction of expectations.
We can deviate in the narrative: “The fire-breathing dragon has cornered the fast-talking donkey. He quips again and again but is destined to be eaten. The dragon’s teeth flash a bright white across the screen. The camera looms over Donkey’s shoulder, showing his minuscule size compared to the beast.” The narrative pathway communicated by the affordances of filmmaking are that the evil vicious dragon eats the Donkey. The expectation is a Donkey Snack. Instead, we Deviate from this Narrative Axis: “Oh, you’re a giiiiirl dragon?!”.
Similarly, ludic deviation: When I walk through long grass in Pokemon’s (Game Freak, 1998) overworld, I know that the next step brings me closer to the Pokemon Centre (to safety). The projected pathway of my ludic experience is “hold up, reach town, heal my ‘mons”. Instead, we deviate: Long grass! The screen flashes with a windmill-like clock wipe, and I’m pulled into a Random Encounter with a different mechanical play experience and new stakes. I have Deviated from the Ludic Axis of controlling my character in geography to a tactical turn-based fight to the death.
In both cases, something triggers[3] that change. Games have inertia, and Newton’s Laws tend to apply here: That inertia continues until acted upon by an external force. In the general case of this blog, external forces are the game’s systems, though individual tables can choose to narratively deviate for other reasons (below).
[3] Triggers are easy to identify in Powered By The Apocalypse Moves (“When you…”), but they are not exclusive to this structure. All rules have triggers (because all rules have a context in which they affect play). The trigger is the part of the rule that tells us in which context it is invoked. This context can likewise be ludic or narrative or both.
So, to recap, we form a Play Axis through norms, expectations, and affordances. We can then Deviate from that Axis. That Deviation is caused by the systems that support play. All levels of play (exogeny, endogeny, and diegesis [Montola, 2009]) contribute to the expectations of the Axis, and all levels can contribute to Deviation from the Axis.
Beyond these established typologies (ludic or narrative; exogeny, endogeny, and diegesis), there is another way to describe these Deviations, which I do not see discussed, but I believe designers need to understand.
Zero or Minor Deviation
Zero or Minor Deviations occur when the ludic or narrative expectation (Axis) is not shifted or shifted in a way so minor as to return to the original Axis quickly and without undue influence. In Dungeons and Dragons (WotC, 2014/24), I can roll to hit the healthy Gelatinous Cube, but the ludic deviation between a hit and a miss is so tiny as to be irrelevant at the scale of the Play Axis. Whether I hit the ooze or not, the next player will do their thing anyway. If I miss, the play experience doesn’t change (in fact, nothing happens, ludically or narratively). If I hit, I might ludically subtract some hit points, but the fight continues like before[4].
[4] You're missing the point if you feel the need to either scoff or defend the design choice at this juncture. Though I do understand that impulse. This isn’t a value judgement that these small deviation rolls “don’t matter” or “aren’t fun”. These Minor Deviation rolls are critical to maintaining pace alongside tension. This will be discussed further in this piece.
Acute Deviation
For those who were rolling character sheets when they should have been paying attention to high-school maths, we’re using the classification of geometric angles here. Acute angles are those smaller than 90°: Those that deviate significantly from the original line but are still heading in (generally) the same direction.
With that metaphor established, our ludic and narrative Acute Deviations are also significant enough to change the Play Axis but not so significant that we leave the gravitational pull of our current experience[5].
[5] Those familiar with my work on ludic influence will understand what I mean when I talk about gravity here (as will those familiar with the concept of guiding constraints in complex systems).
An acute deviation can manifest like Shiver From Fear from Bluebeard’s Bride (Magpie Games, 2017).
When you shiver from fear, name the thing you are most afraid will happen; the Groundskeeper will tell you how it’s worse than you feared. Keep the ring and choose two, or pass the ring and choose one:
It infects the Bride with its perversion.
It has the Bride in its clutches right now.
It speaks to you. Take one trauma... Just you, Sister.
Shiver From Fear cannot return the game to the original Axis once invoked. Something must shift. If the player retains the ring[6], one of their two choices will shift the momentum and stakes of play in a narrative sense. There is a deferred option (Take One Trauma), which doesn’t deviate the Axis, but to select only that consequence, the player has to relinquish control of the ring, which inherently creates Axis Deviation [7].
[6] “A Sister [player] who wears the ring has more narrative control over the actions of the Bride” (ibid pg 8). Holding the ring offers the player decision-making authority in some phases, and “ring moves”, special moves that direct the flow of play (ie define the Axis)
[7] Each Sister/Player has different ludic levers (stats, special moves) and different narrative motivators, so placing a different Sister in the decision-making position alters the Play Axis.
The key to Acute Deviations is that they change the Play Axis, but still feel familiar and maintain momentum because the change remains in the same sphere of play[8]. In Bluebeard’s Bride, the trigger is a fearful description, which occurs when the game’s Axis is heading toward the desired horror tone. The Deviation accelerates the danger (“in its clutches right now”), shifts the narrative of the Protagonist in the direction of the trigger (“infects the Bride”), or ever so slightly alters the tone toward a different horror tone (by changing the holder of the Ring). But that new Axis rhymes with the original’s creeping horror.
[8] Spheres are here used in the sense first identified by Nellie Seale during her work with Melbourne Megagames. To quote from her unreleased notes: “[…] multiple different sub-games or spheres of play, focusing on different parts of the game world or mechanics, and offering different gameplay experiences”. While Seale’s notes on Spheres are exclusive to Megagames, I would gladly assert their existence in other game genres without hesitation.
Acute Deviation changes the game at hand (at least significantly enough to change the Axis) but remains so close as to collaborate with preceding play.
Perpendicular Deviation
Where an Acute Deviation maintains play within the same sphere but shifts focus, “Perpendicular” describes a Deviation considerable enough to depart the preceding sphere of play. However, this Deviation is not a refusal of the original Axis; it’s simply a change in focus. A typical self-evident example that comes to mind is a failed Stealth check leading to Combat. The macro end-goal is still the same (the characters move to the next room, find the object they seek, or spend resources to traverse the overworld), but the pathway to get there has fundamentally changed (as has the ludic and narrative structures that we’re engaging with, and thus our Axis!)
In the earlier example of moving from the overworld to the random encounter in the Pokemon or Final Fantasy series, we are still progressing through the games’ core pathways (“traverse the overworld”, “explore”, or “progress”), but the ludic expectations that we have dramatically shift between the before and after of the Perpendicular Deviation (do combat with characters’ lives at stake).
A more narratively Perpendicular example is the final card of For The Queen (Evil Hat Games, 2019/2nd edition, Darrington Press, 2024). Throughout the game, players establish a power relationship with The Queen, which heads toward a particular Narrative Axis: The Queen owns you (or she at least holds some power over you, placing your character in a subservient position). The final card of For The Queen (“The Queen is under attack. Do you protect her?”) adds a new narrative context to the game[9]. This is a Perpendicular Deviation because it isn’t refusing the narrative or ludic Axis (the Queen still has a title and some form of constructed power over your character). Instead, it offers a recontextualisation through a different sphere (yes, she owns you, but without you, she may not survive).
[9] This Narrative Context is “new” in the sense that it explicitly adds some form of immediate conflict, which the player characters can affect (which is not the case for other prompts), and new in the sense that the power relationship with the Queen is altered or inverted: She is a victim, and your character has the agency.
The new Axis may “rhyme” or approach similar content or genre, but it doesn’t necessarily agree with the preceding Axis. If Acute Deviation is said to be in collaboration with the preceding play, then Perpendicular Deviation is in conversation.
Perpendicular Deviation tends to reduce play’s momentum drastically and instead spike the novelty. In our example of For The Queen, players need to pause and think about this changing situation, but the elation of the final (expected) card buoys us. In Final Fantasy, we lose our sense of orientation to the world map and our eagerness to get to the next weapon shop but are elated to do some cool, risky combat.
Obtuse Deviation
Sometimes, conversation isn’t enough! Sometimes, the Axis has to be thrown away! In these cases, we see Obtuse Deviation.
Consider Spike Drills from Stars Without Number, Revised Edition (Crawford, 2017), which lays out the process for jumping a Spaceship across the known (or unknown) universe.
Spike Drills: […] A ship’s navigator can make an Int/Pilot skill check to make a successful spike drill […] If the roll fails, something has gone wrong on the drill, and a roll on the failed navigation results are necessary. These mishaps don’t normally result in the summary death of the crew, but they often force the navigator to make emergency course changes or drill exits that might leave the ship in a dangerously unfriendly region of space […]
[A Spike Drive Failure may also result in] Catastrophic dimensional energy incursion. Ship emerges around a star within 1d6 hexes of the target destination with drive and all systems destroyed.
This rule is triggered when players narratively want to travel to a goal location and ludically engage in a step-wise check of their preparation[10] to reach it. Rather than being in collaboration or cooperation with this Axis, a catastrophically failed Spike Drill is in direct opposition — and not only in opposition but with such ferocity that it shifts the Axis in tone and gameplay. All systems destroyed around a random star?! So long Axis of Play! Whatever you’ve prepared isn’t what the game is about any more. Now you’re playing the Adrift In Space with 12 Days Worth of Oxygen game. The Axis has changed from measured exploration to catastrophic recovery.
[10] The Axis here is paced and preparatory. Slowly leveraging known resources that have been collected over time. The Design enforces this by having the Spike Drill rule be a series of questions (like the Engagement Roll of Blades in the Dark), which creates steps as short-term goals for players and pays that off with a cumulative roll assessing all of these preparatory factors.
The momentum of the game is now, literally, dead in the water. What do you do now? How are you going to play this out? It doesn’t have a lot of impetus, but it’s novel as HECK.[11]
[11] The “Failed Jump is the New Game” Deviation is not uncommon in sci-fi games like Worlds Without Number or Traveller. An anecdotal version can be heard on Happy Jacks Podcast, Season 34, Episode 01.
Deviation is Outcome-Dependent
As Deviation is based on the outcome, a particular rule can have different Deviations depending on which outcome is selected. Using our previous example: Jumping across the universe successfully offers acute deviation (we change geography as intended and proceed), while jumping across the universe unsuccessfully offers obtuse deviation (as we draw straws to see who we space first in order to save oxygen).
It is worth cautioning that having a move that could present minor deviation or obtuse deviation dependent on a dice roll is….a brave design choice.
Cumulative Deviation (The Killing Blow)
A series of slight deviations can add up to a larger one. For a simple example, consider that D&D combat rolls are Minor Deviations (see above), but if the right combination of hits and misses occurs, it could result in a TPK[12]. The cumulative effect of those Minor Deviations is an Obtuse Deviation that dramatically shifts the Play Axis away from the previous direction. This shift usually leads to some form of dramatic loss within the story (a “bad ending”/loss state) or a drastic change in narrative focus (advancing time forward to a new group of heroes, or following the original characters into an afterlife are common options. 13th Age (Pelgrane Press, 2013) formalised this into the Campaign Loss.
[12] Total Party Kill - A term for when all player characters are killed in the same encounter, usually indicating a failure-state or substantial change in play Axis.
Campaign Loss: If all of the other players agree, the heroes beat a hasty and successful retreat, carrying any fallen heroes away with them. In exchange for this extraordinarily generous retreating rule, the party suffers a campaign loss. At the GM’s discretion, something that the party was trying to do fails in a way that going back and finishing off those enemies later won’t fix. If the heroes were on their way to rescue a captive from unholy sacrifice, then naturally enough the captive gets sacrificed. (13th Age, Pelgrane Press, 2013)
In the Campaign Loss, one rule is used. A D&D 5e fight may take several different arbitrations through Minor Deviations. Both create an Obtuse Deviation.
In the same way, Multiple Obtuse Deviations can also loop play around to return to the original Axis. This move is a favourite of particularly disruptive PbtA movesets. I often love when, in Blades in the Dark , I employ an Obtuse Deviation as a result of a failure (eg She stabs you right in the guts and then leaps off the balcony. You lose the opportunity to catch her, and you now have level 3 harm — Major ludic and narrative shifts) and a player shifts in right back to me (eg She stabs me, but I have my cohort of thugs waiting in that alley she just jumped into. If they can hold her for just a few seconds, I’ll be down there and we’ll have her outnumbered). The two swings bring us to roughly where we would be with an Acute Deviation of the roll in the first place.
A Softening of Opinion
With that in mind, it is with some kindness that I look to D&D’s small deviations around combat actions. Imagine a D&D combat with all of the same expectations (5 or so players, roughly 3-5 actions per player, over the course of 70-120 minutes of playtime). Now imagine this combat with every action introducing obtuse deviations. After the first round, we would have 5 or more significant changes to the expectations of our play. It’s closer to the mad hatter’s tea party than a game. There’s nothing for players to invest in, and there is no capacity for the expectations of play (the Axis) to develop. Without that Axis, actions lack meaning, and our play falls apart.
It is also with some kindness that I look at the OSR approach to “Save or Die” (or, more recently, “Save or Suck”) rules. In these cases, the player has a single chance to take action. If they fail to resolve the situation effectively, they create obtuse deviation (including character death). A character saving against Finger of Death or Sleep offers an opportunity for Deviation: How does the battle change with one or more of your colleagues incapacitated (and not in that friendly way where you can heal them 1hp, and they pop right up)? And yes, there are significant problems with Save or Die/Suck effects that make them poor design choices. Still, as a feature of Deviation, I can see the benefit of removing momentum and introducing a novel state of play through this kind of system.
