thoughts on Apocalypse World?

[pemerton]

So to take one of your examples and run with it....let's say the PCs are actively trying to determine a culprit because an ally of theirs has been arrested for a crime. Even something as fundamental to this situation as "did the ally actually commit the crime" is likely unknown when play begins. The ultimate outcome is determined through play, and how the rolls go and what they lead to; it's not decided ahead of time.

So it can go either way......perhaps the ally was framed, perhaps they committed the crime. You'll see the phrase "Play to find out" and that applies to the GM, too.

Right. I gave the imagined example, upthread, of the PC going to Isle's car shed only to find that she's not there, but her cap is lying on the ground and the car is missing.

Has Isle been kidnappd? Has she eloped? Maybe the GM knows, and has even set up a countdown till the kidnappers kill Isle clock. Maybe the GM doesn't know. It makes no difference to the application of player-side moves. And the only difference it makes to the GM is that instead of simply saying what honesty demands s/he also has to say what prep demands.

One additional thing - there often is a move, you just need to think of how to apply it. Because the move should force you to set up a dramatic situation.

Right. I posted about this in detail not too far upthread.

Vincent Baker calls out most of the moves in his Moves Snowball example of play, but not all of them. Eg when he narrates to Marie's player that she finds Isle and friends sitting on the roof of the car shed, this is offering an opportunity. But the example doesn't call that out. I riffed off this in my own Isle example (post 223) by imaging that the GM move is, instead, to announce offscreen badness by narrating that Isle is not there, the car is gone, and her cap is lying on the ground.

@Faolyn, I feel that you are not really taking seriously the notion that everything the GM says is a move, made in accordance with the principles. And that those moves - because they involve concepts like badness and opportunity with a cost and their stuff's downside and consequences but also can be opportunities without a cost - require a value framework. Is it good or bad that Isle should be missing? In @Campbell's example, is Rorik finding the dead body an instance of badness ("there's a killer on the loose") or an opportunity ("cool, now I've got the corpse and recently-living brain I need for my workspace!")? We can't tell what is bad and what is a cost and what is a downside and what is a (meaningful) consequence until we have a framework for evaluation. That framework is provided primarily by the players. Which goes back to @chaochou's remark about the players setting their own agenda.

Treat what like a gift how? What is the It that should be brought? What moves should or could be made? I literally am not understanding what you mean here, and using slang doesn't help.

@Campbell is using the word "gift" in the same way that Vincent Baker refers to a player providing an opportunity on a golden plate - the GM is expected to respond by making an appropriate move, consistent with the agenda and principles, as I and @Blue have explained in our posts.

And how would I be mindful of my fronts in this situation? How would giving clues make things impersonal? What moves fit my principles, and are you talking about my principles as a player or as an MC? What if Rorik wants to look for clues to find out who actually killed Plover? Do I just give him a bunch of clues, or does he have to roll, and if so, what does he roll--since apparently it's not Read Sitch and there's no basic investigation skill.

I think these questions show that you are not taking seriously what the AW rulebook says.

Your questions suggests that you are envisaging play very similar to trad CoC play - the GM has all the backstory worked out (who did what to whom when) and then the players, via their PCs, are identifying clues that will reveal that backstory. But AW does not approach RPGing in that fashion. There is not a single AW principle or move that talks about clues, so we can't use that as an analytic category to explain AW play. But there are moves that talk about announcing badnes, be that future badness or offscreen badness. I showed, in a post above, how that move could be used to frame a situation in response to a player's action declaration that does not trigger a player-side move: ie the player declares that their PC goes to find Isle at the car-shed, and the GM responds by telling the player that Isle's not there but they (ie their PC) can see that the shed has been broken into, the car is missing, and Isle's favourite cap is lying on the ground.

I also explained how, if the player were now to have their PC look around, that would be reading a charged situation and I talked a bit about how the GM might make moves in response to the results of a read-a-sitch roll.

But making any of those moves requires knowing what would be bad, or an opportunity, for this (these) PC(s) in this context. Which is why the play of the game is inherently personal.

If I'm running D&D, the player can ask "what's the general mood like" or "who's the baddest mofo in the room," and I can tell them to roll Insight. Or I can tell them to roll Insight as soon as they enter, or just use passive Insight. If the player asks if there are any exits, I can have them roll Perception, use passive Per, or for that matter, simply tell them there's another exit as soon as they need to escape out of one. Or if one of them says "Is there a back door? If there is, I'm going out it," then I can either say there is one, say no, or invent a back door right there and then. Ditto for GURPS, Fate, Cypher, and other systems I've played.

I quoted the rulebook discussion of this (p 200) upthread. And it is rehearsed above in this post, and also in Blue's post.

A player in AW can ask "What's the general mood like?" Assuming the situation is not charged, this does not trigger a player-side move. So the GM responds by making a move, as the agenda and principles dictate. Because I don't know anything about your player, and your fiction, I can't in this post speculate as to what an appropriate move would be. But I've given many examples in my posts upthread of what such moves might look like.

Since AW indicates that the MC sets up things like groups of opposition, rival gangs, and other stuff like that in a sandbox-y type of way, I would imagine that it would be perfectly in-game for me to say "this noble is having a masquerade tomorrow night, there's been a rash of muggings on this other street, there's been reports of demons on such-and-such a street, the glow-in-the-dark fungus farms are mysteriously failing, and you all have personal issues you said you want to deal with--so what do you want to do now?"

No. What you have described here is not a MC move.

Unless you're saying that the GM doesn't actually set up anything, including the area's NPCs, until the players decide they exist? If otherwise, then AW should just say that it's a sandbox game.

I don't think we can profitably discuss how fronts are authored and used at this point of the conversation. At this stage you're still not taking seriously that the MC makes moves in accordance with the principles.

It makes it sound very GM vs. PC to me. "I want to hurt the PCs, but I'm not allowed to do it unless I have a good in-game reason." I'm sure that's not what's intended, but the writing is so unclear that's what's coming across.

I've got no view on whether or not you should play Apocalypse World. But if you want to understand the play of the game, I encourage you to stop thinking about "how it sounds" and read it literally having regard to the principles. None of the principles says hurt the PCs. But the principles do say to (inter alia) respond with f*****y and intermitten rewards. And the way this is done is by making moves. The only move that (literally) hurts the PCs is to inflict harm, which a GM would do if the dynamic of play warranted a hard move (as per my quote upthread about the dynamic of soft and hard/irrevocable moves) and if that followed from the fiction - eg it was established in the fiction that the PC is being targetted by a sniper, or is being beaten up by a thug, or whatever.

The only options that require roles are both manipulative (and one of them I am not interested in doing at all), and the lack of a persuasion-type move makes everything both arbitrary and dependent on aggressive activity. If the MC decides one thing, then there's nothing the player can try to accomplish peacefully.

I honestly don't understand what you're describing here. There are too persuasion-type player-side moves: one based on the threat of violence (go aggro) and one based on the offer of a quid quo pro (seduce/manipulate). If the player declares some other action, like just a simple request of an NPC, then - as per what I posted and Blue posted - the GM makes an appropriate move in response, where appropriate means in accordance with the principles.

Some further responses, to other parts of your post:

It looks to me like the MC is railroading this: Keeler will walk by the armory and she will not only hear people in there but will automatically go inside and find out what they're doing.

This is not railroading. It's framing - the GM is telling Keeler's player where Keeler is and what she notices. It's exactly the same as the D&D GM saying, "OK, so when you all meet back at the inn . . . ".

If there is some reason why Keeler's player thinks that Keeler would not be at the armoury, now would be the time for her to explain that - similar to the discussion that the example sets out of the GM and Marie's player discussing where Marie is. But for what I think are understandable reasons, Vincent Baker has skipped over such a possibility.

But if the MC is actually expected to just tell PCs where they're going, what they're doing, and also that they know info that they couldn't possibly know, because this allows the MC to ramp up the tension, then I think they're doing it wrong. Or at least in a way that discourages me from wanting to play.

I think Baker's thought is that describing to Keeler what she hears from her gang members as she wanders past her armoury is no more controversial than - for instance - a CoC GM telling the players what letters their PCs received in the morning mail. That assumes that the PCs in fact went out and checked their mailbox, but normally that assumption would not be controversial.

AW has no random determination of the fiction. At every point someone has the job of deciding what the fiction is: either a player is saying what their PC does, or the GM is announcing backstory, or framing, or consequences.

OK, so how is this different from a typical RPG?

Here are some examples of random determination of fiction, chosen from various RPGs:

* In AD&D, a failed roll to pick locks means that the thief failed to pick the lock.

* In 3E D&D, a certain degree of failure on a climb check means that the character falls.

* In Rolemaster, there are many many crit results (far too many to spell out in a post) that dictate what injury is suffered by the victim of violence.

* In classic D&D, a wandering monster roll determines who/what the PCs encounter.

* In 5e D&D, a failed save against a Charm Person spell tells us that the target of the spell has been ensorcelled by the caster.​

These examples could very easily be multiplied. There is nothing like this in AW. All the fiction is deliberately authored; but there are rules that establish who gets to author it when, under what constraints.

 

[pemerton]

I haven't played Traveller so I can't speak to that (although I looked it up and the SRD lists Carouse, Investigation, Streetwise, Social Sciences (Psychology), and Tactics, all of which could be used to read a situation). And it has a Diplomat and Persuasion skill.

I'm replying to this in a separate post, because it is only tangentially relevant to Apocalypse World.

In Classic Traveller, the list of social skills is Admin, Streetwise, Bribery, Broker, Gambling, Steward, Carousing, Liaison, Leadership, Recruiting, Instruction and Interrogation. But that doesn't mean there is a sub-system for Reading a Situation. I can assure that there is not.

There are various subsystems for encounters, and for determining reactions. There is a set of interlocking rules (set out at various places in Books 1 and 3) for determining whether and when PCs find themselves interacting with officials, and whether those officials harass them or inspect their documents closely, and whether bribe attempts will work and whether forged documents will be picked up.

There is a system (found in Book 4) for recruiting mercenaries, and Recruiting skill factors into that. Leadership is a factor in morale and surprise.

I think you are tending to look at all RPGs through the paradigm: the player sets what their PC does; the GM asks for a check modified by some appropriate stat or skill bonus; and depending on that result and the GM's view of the fictional situation, the GM decides what happens next. But that is not how Apocalypse World or Classic Traveller works.

 

[chaochou]

There was nothing about his tone or content in his post that required escalating the hostility.

There's no hostility!

But there is frankness, and there is also some frustration when answers are already there but are completely blanked if they don't fit preconceptions.

Good faith has to include genuine open-mindedness, including to ideas such as:
There's no need in 'mystery' play for one participant to have pre-written an answer (or answers) to the mystery. Fantastic play can stem from situations which are a mystery to everyone playing, including the MC.

 

[Fenris-77]

Something to keep firmly in mind here as we slide back and forth between AW specifically and PbtA more generally is that the design choices made for those games are not all the same. The decision about, for example, what moves to include is a direct design choice based on what kind of conflict the designer wants to be the focus of the game. Baker makes this pretty clear is his series of blog posts on the AW engine as a design tool. So for AW, the kinds of conflict Baker wanted the game to focus on is not at all mystery solving, and so the moves available reflect that. What Baker did want the game to focus on is interpersonal conflict (among other things), and the moves again reflect that design choice. He describes moves, as an idea in Powered by the Apocalypse, thusly:

I also said that the basic moves give structure and a certain order to the players’ conversations: who asks questions and who answers them, what you should say yourself and how you should treat the things that the other players say. I called it “permission and expectations.”

Anyway, my point was that with different design choices come different ways the 'conversation' of the game is shaped. PbtA certainly can do things like persuade and some of the less aggro social interaction type things when that's something the designer wants it to do. Even then, the focus is still going to be about conflict though. In terms of what that looks like for a police procedural I think it's helpful to think about a show like Castle, or really any decent investigative show. What moves the narrative along (the conversation of the game for our purposes) is interaction between the characters as they bounce off each other, and conflicts that arise in the course of solving the mystery. Pretty much any example of an episode will feature rising stakes and snowballing complications. These conflicts sometimes take the form of tension with superiors (like in X-Files, say) or could be direct conflict with a bad guy (too many examples to mention). Even when the characters find clues, there are stakes. Will they find the killer in time? Will side character X get got? How many rules will be broken and what will happen as a result? And so on and so forth. PbtA can do all those things just fine, and in a game specifically designed to spotlight them would do extremely well.

That's my two cents anyway, and I hope my explanation is cogent. I haven't had my coffee yet, so no promises.

 

[GrahamWills]

There's no need in 'mystery' play for one participant to have pre-written an answer (or answers) to the mystery. Fantastic play can stem from situations which are a mystery to everyone playing, including the MC.

Glad you have finally realized that this is what I have been looking for and others have indicated. PbtA has been fun in a lot of situations, but, even with fantastic GMs (of which I have had several) it doesn’t work as well in the situation where there is an established fact that a character needs to discover.

This is not to say that Scooby-Doo doesn't involve solving mysteries, but, instead, that we watch Scooby-Doo because we are interested and invested in seeing Fred, Velma, Daphne, Shaggy, and Scooby-Doo do it.

I only quoted this part, but I strongly appreciate your long description of Monster of the Week plays; I have not read the rules book, only played it, so it was very illuminating.

Maybe I should explain why I’m spending time on this convo; I’ve played and run a lot of systems; probably 30+ or so that I’ve had at least mini-campaigns with, from Rolemaster and AD&D to DitV, Fate, Tri-stat, Doctor Who, Kids on Bikes, and Everway. PbtA games look absolutely excellent to me; I love the presentation, the base concepts and the compactness and ease of getting started. Specific sub-systems I have lifted for other games I run. So I have been continually surprised when my play experiences have not been as much fun as I would expect. I’m not in the camp that likes to run one system for all genres — I used Savage Worlds for my Flash Gordon campaign even though I think it’s a bit of a clunky system in general, because it fits the pulp sci-if genre so well. So my goal is to work out when I should consider PbtA.

And this thread has been helpful. I think the quote from @Aldarc might be a good summary — it occurs to me that one-shot investigations, which are typically more about enjoying the mystery and less about the characters might be less good a showcase for PbtA than a campaign, which is typically character-focused (at least for our group).

But I still wish Magpie had picked a different system for Avatar …

 

[hawkeyefan]

Thank you, @hawkeyefan, that helps my understanding. I know the style of investigation where there is no pre-existing puzzle and the group comes up with a solution is a way of running investigation, and I can see that PbtA can handle that. For me and my group, that always feels a little illusionistic — you are going to solve the problem eventually because you will generate a solution. But more importantly puzzle-solving is core part of RPGs heritage, so it’s helpful to know that PbtA is just not going to be the best tool for such a game.

I don't think "solving the problem" is a certainty. The resolution of the situation (in this case, the revelation of who done it) is going to come about as a result of play, but that doesn't mean that it will go the way the players want. Far from it.

If the entire point of the scenario is a murder mystery style whodunit, then it may not be such a good match. But it depends on which specific game you're playing, and a lot of other factors.

So just to kind of offer an example that's not an RPG......there's an old show called "Columbo" and it's about a detective solving a mystery. But it's different than many detective shows because the show starts by showing you exactly who did the deed. Who did it is never in doubt; instead, the show is about how Columbo pieces things together in order to figure it out.

That's very different from your classic detective scenario where the entirety of the fiction is building toward the revelation of who's guilty. It approaches the idea of detective fiction from a different angle than what's typical.

So I think you have to approach a PbtA game similarly. The point is less about who did it than it is about the fallout of the whole event, so you should proceed with that in mind.

I’ve most enjoyed PbtA in highly railroaded settings (Bluebeard‘s Bride) and also in sandbox-y settings where there is opposition that need to be overcome in imaginative ways, but not by trying to figure out clues. I can’t imagine effectively using PbtA to run the Call of Cthulhu games I played at Origins last week, but I would also be unenthusiastic about trying a caper action scenario using BRP. I’ve played MONSTER OF THE WEEK a couple of times — would it be fair to call it the closest PbtA version for investigatIve roleplaying, or is there any other implementation I should look at?

I couldn't say for sure, honestly. There are so many PbtA games now that it's possible there are some that tackle mysteries in a more direct manner. I know Monster of the Week by reputation only; I've never played it and only read a bit of it. My understanding is that there are moves about uncovering facts and lore that you may expect in this genre (I'm thinking of the show Supernatural and the like, where the protagonists need to learn of the monster's vulnerability or some such in order to prevail).

I can say that I ran a Blades in the Dark campaign that deviated from the norm in that it used the Bluecoat and Inspector playbooks (which are the Cops and Detectives of that setting) rather than the standard Scoundrel playbooks, and that took some different approaches to play and GMing. I'd say that campaign was very much a learning process for me as it forced me to come at police procedural elements in a different way in order to make them interesting as a game.

The Between is a new take on PbtA and it incorporates rules on how to implement mysteries which is in turn lifted from the Brindlewood Bay game (which is basically Murder She Wrote meets Cthulhu). I haven't run that game yet, but its approach to mysteries may be what you're looking for. @Fenris-77 is pretty familiar with those rules, so he may have more to offer about that game specifically.

 

[Grendel_Khan]

Thanks @pemerton for humoring me with that FitD question that I directed at you. I think your example of seeing the culprits driving away is a great Lost Opportunity consequence.

But if @Manbearcat and @Ovinomancer and whoever else might be a Blades/Forged in the Dark veteran can humor me further, here are some situations that came up in the test session I ran last night of Scum and Villainy in a Star Wars setting. I fully believe that I was GMing a ton of stuff wrong, given the FitD system/approach, so I'm not looking for attaboys or reinforcement.

Some quick context:

-Scum and Villainy differs from Blades in that you have a ship instead of a crew, and so you aren't generally tied to a given area. It's not a bounded sandbox, like wth Duskvol. If anything it's the opposite, making it (in theory) a good fit for Star Wars, where you have lots of interstellar mobility. This changes a lot of things, including making something like that very compelling setup that Manbearcat laid out less possible, imo. You take jobs because someone is paying you, and those could be in lots of places.

-For this test session I may have broken the premise without realizing it--my main interest was to get practice with the core mechanics, and I wound up having my solo player, who chose a new Jedi for his character, and his more experienced Jedi partner NPC assigned to hunt down a supposed terrorist. Did kicking things off unrelated to PC contacts and faction relationships make everything that following invalid or at least clumsy? Maybe so.

I'm not (I hope) doing the dreaded listen-to-my-session thing, but here are the specific moments/decisions I'm curious about:


1) Based on a roll to learn the terrorist's whereabouts from local criminals--the player rolled a success with consequence on a risky Command action to intimidate them--I figured they were now being led into a trap. So they took a boat to another area of the city where the target was supposedly staying. This being a one-shot test session, in which I very much wanted a noir-ish moment where the newbie's more experienced partner gets killed, I figured the trap would start big, with an A-Wing attacking the boat from far above--a kind of sniper situation. I said that they could hear a high-pitched keening sound during the boat trip, but my player did nothing (he's also new to playing FitD, though not reading it). When he stepped off the boat I triggered the attack.

At this point I suddenly didn't know what to do, because in theory the Attune action specifically notes that you can use the Way (aka the Force) to "sense unseen danger or killing intent." But the player didn't initiate that action upon hearing the suspicious noise. So we awkwardly decided he could use Attune now to sense the attack and try to get himself and his partner off the boat in time. He rolled a critical success (two sixes) so he decided to pull the boat's driver off as well.

Everything about how I handled this seemed wrong, and in the moment we were left with the sense that if the player just kind of waits out a situation instead of taking action, maybe that's on them, because, as discussed in this thread, passive actions--especially the sort of passive Perception rolls that are almost constant in many trad games--just don't make sense in FitD. But what do you guys think? Was this just a hopelessly trad and off-base encounter from the start? And how do you handle stuff like danger sense or similar unnatural/enhanced perception in FitD, if it seems like an ambush has become part of the story?


2) The player and NPC decided to get to a rooftop to deal with the A-Wing assassin, and here, again, I may have defaulted to a trad situation. I said that as they were running into a building and about to get into the stairwell, a pair of guys entered from the street and immediately pulled blasters and opened fire--evidence that the trap was bigger/worse than expected. The resolution for this was simple and fast and great. But was having these two shooters pop up (to show the escalating danger and stakes) sort of a game-breaking trad intrusion, because it wasn't based on another, post-A-Wing-attack player roll and related consequence? This was, in other words, a GM-first piece of fiction, which would miss the point of FitD, right? Or am I just in my head with this one?


3) Finally, toward the end of the scene/session, the PC and NPC realized they were stuck, with the A-Wing loitering above the roof and a large group of people running up the stairs. How this situation was resolved was, again, very cool to me, and pushed me even harder toward wanting to do lots more FitD. But as with the earlier appearance of the two shooters, this horde of dudes did not appear based on a subsequent player roll or suggestion. Does that once again break the core FitD approach, and make the game about PCs reacting to GM-determined fiction, instead of the other way around? Or am I looking at this in a way that's too zoomed in, and really the whole situation is just flowing from the player's chosen approach for how to find their target, and the consequences that followed?

 

[Fenris-77]

OK, a quick(-ish) precis of the Brindlewood Bay mystery mechanics, which are pretty much ported directly to The Between, which is otherwise mostly PbtA in terms of design ethos and mechanics. I'll use the verbiage from The Between because that's the iteration I'm most familiar with.

So, every threat in The Between (think of a threat as similar to a monster in MotW) has 20 clues written for it as well as several questions (the answers to which 'solve' parts of the mystery, and are called Opportunities) and which have a complexity of (mostly) 2-8 and also the aforementioned associated Opportunity.

The clues are evocatively and specifically written to scaffold and enhance whatever the theme of that particular threat is. So a threat based on a fire-starting ghost would have a lot of smoke, flame and whatnot sorts of clues. Finding clues is a product of several moves in the game but primarily the Information move (a pretty standard 2d6 PbtA roll with the 6-/7-9 and 10+ results). There is another move called Answer a Question where the players have a freewheeling conversation about how the clues they have might fit together and posit a theory about a question from the threat, at which point they roll (standard 2d6 again), adding the number of clues they have found and subtracting the complexity of the question. On a 10+ their theory is correct, on 7-9 its correct but with added danger or complications, and on a 6 or less it's incorrect and more clues must be gathered.

The mystery in this system comes from the interplay of evocative places and people, and how the characters chose to approach the mystery at hand. The clues aren't tied to locations, but are given as the result of a successful roll, so what's important there is the framing of both the investigation and the clue in terms of fictional positioning (the Gm decides that clue would make sense/be awesome here). As you can see there is no pre-determined answer for the players to find, just a series of questions that help frame the mystery rather than solve it. When they answer a question successfully they get to frame the opportunity, which answers part of the mystery and then move on to the next question. Most threats have two or three questions, so this isn't an interminable process.

This can all seem a little nebulous without an exemplar, and I have a couple of threats lying around I can show as examples if anyone's interested. The Between a very cool system and I have nothing but wonderful things to say about Jason Cordova, the author.

 

[chaochou]

I fully believe that I was GMing a ton of stuff wrong, given the FitD system/approach, so I'm not looking for attaboys or reinforcement.

Caveat: I don't know Blades well and I don't know Scum & Villainy at all, except by reputation. I don't own it and haven't played it.

But I had an overall impression, reading your play notes which wasn't to do with the GMing but the sense of fairly passive play which in turn led you to try and move things forward.

It sounded like a player who didn't quite trust that they were actually meant to be making things happen and so was waiting for you to. Your instinct that you should be responding to the player character is correct in principle, and passivity is one of the toughest things to deal with.

I went through this exact problem with my group and it was a headache because you can't force people to be pro-active - it's an oxymoron. Being proactive can take a while to click for players.

But it's also why game set-up, character and setting creation, the establishing of situations which fire the imagination of the player(s) and the immediacy and urgency of player goals are so important. The better you can do that as a group, the less chance you have of players waiting for the MC to drive play.

 

[Aldarc]

I only quoted this part, but I strongly appreciate your long description of Monster of the Week plays; I have not read the rules book, only played it, so it was very illuminating.

Glad to help. As the conversation drifted to running investigations, this seemed like a potentially good illustrative example.

Maybe I should explain why I’m spending time on this convo; I’ve played and run a lot of systems; probably 30+ or so that I’ve had at least mini-campaigns with, from Rolemaster and AD&D to DitV, Fate, Tri-stat, Doctor Who, Kids on Bikes, and Everway. PbtA games look absolutely excellent to me; I love the presentation, the base concepts and the compactness and ease of getting started. Specific sub-systems I have lifted for other games I run. So I have been continually surprised when my play experiences have not been as much fun as I would expect. I’m not in the camp that likes to run one system for all genres — I used Savage Worlds for my Flash Gordon campaign even though I think it’s a bit of a clunky system in general, because it fits the pulp sci-if genre so well. So my goal is to work out when I should consider PbtA.

I think that the goal in bold is an incredibly interesting issue that doesn't always get discussed in "system matters." It's not just a matter of how or whether system matters, but also when should one consider one system over another for play purposes, in this case PbtA. I don't have an answer on hand for when one should consider PbtA, but I will definitely be mulling this over.

And this thread has been helpful. I think the quote from @Aldarc might be a good summary — it occurs to me that one-shot investigations, which are typically more about enjoying the mystery and less about the characters might be less good a showcase for PbtA than a campaign, which is typically character-focused (at least for our group).

I have had a similar issue with trying to find the "right system" for a back-burner game that I have wanted to run, which incidentally involves a supernatural investigative society in 1840s Vienna. So I have looked into a variety of potential investigative or urban fantasy games for those purposes: e.g., Call of Cthulhu (Berlin), Gumshoe, Fria Ligan's Vaesen, Dresden Files Accelerated, Monster of the Week, etc.

Edit: This thread has also now made me aware of The Between, so... crap... the list grows.

But I still wish Magpie had picked a different system for Avatar …

PbtA is really their system of choice and Magpie Games know it inside and out, so it's little surprise that they convinced Nickelodeon that this system would fit their IP. It seems like an incredibly appropriate system for Avatar, especially after Magpie proved themselves at handling young adult fiction with Masks.

The only other systems I probably would have considered for Avatar would have been Fate (which includes games like Do: Fate of the Flying Temple and a Korra-like Jadepunk and it even uses a mock Avatar character in its Accelerated book) and Cortex Prime (see The Dragon Prince: Tales of Xadia), or possibly something like Kids on Bikes/Brooms and that's pretty much it.