Vincent Baker in his blog series on drafting PbtA games says—

A crucial feature of Apocalypse World’s design is that [its concentric] layers are designed to collapse gracefully inward:
• Forget the peripheral harm moves? That’s cool. You’re missing out, but the rules for harm have got you covered.
• Forget the rules for harm? That’s cool. You’re missing out, but the basic moves have got you covered. Just describe the splattering blood and let the moves handle the rest.
• Forget the basic moves? That’s cool. You’re missing out, but just remember that 10+ = hooray, 7-9 = mixed, and 6- = something worse happens.
• Don’t even feel like rolling the dice? Fair enough. You’re missing out, but the conversational structure still works.

In the 2015 game, Spirit of 77, David Kizzia and Bob Richardson specify a basic move—

Often during a role-playing game, disputes will come up: What happens next? Who is successful? Where did they go? To resolve these issues, we have one simple rule: If it’s important, roll the bones (or dice).

The Basic Rule
1) Describe what you are doing, then roll two six-sided (2d6) dice and add the results.
2) If the result is 10 or higher (10+), it is considered a full success, and your character does exactly what you described.
3) If the result is higher than six but lower than ten (7-9), it is considered a partial success, and you either partially succeed in your task or you succeed with a cost.
4) If the result is a six or lower (6-), it is considered a failure, and you fail to get the results you want, plus the DJ can take actions against you.

That’s it. You can play Spirit of 77 just fine using only this rule. Everything else in this book expands on this simple idea to give you more options and to cover specific situations, but if you want to play super fast and loose, this is the only rule you really need.

In contrast, Dungeon World codifies a default or catch-all move, with its only move that lets the player pick which stat applies—

Defy Danger
When you act despite an imminent threat or suffer a calamity, say how you deal with it and roll. If you do it…

• …by powering through, +Str
• …by getting out of the way or acting fast, +Dex
• …by enduring, +Con
• …with quick thinking, +Int
• …through mental fortitude, +Wis
• …using charm and social grace, +Cha

On a 10+, you do what you set out to, the threat doesn’t come to bear. On a 7–9, you stumble, hesitate, or flinch: the GM will offer you a worse outcome, hard bargain, or ugly choice.

And the commentary on the move—

You defy danger when you do something in the face of impending peril. This may seem like a catch-all. It is! Defy Danger is for those times when it seems like you clearly should be rolling but no other move applies.

Defy Danger also applies when you make another move despite danger not covered by that move. For example, Hack and Slash assumes that’s you’re trading blows in battle—you don’t need to Defy Danger because of the monster you’re fighting unless there’s some specific danger that wouldn’t be part of your normal attack. On the other hand, if you’re trying to Hack and Slash while spikes shoot from hidden traps in the walls, those spikes are a whole different danger.

Danger, here, is anything that requires resilience, concentration, or poise. This move will usually be called for by the GM. She’ll tell you what the danger is as you make the move. Something like “You’ll have to Defy Danger first. The danger is the steep and icy floor you’re running across. If you can keep your footing, you can make it to the door before the necromancer’s magic gets you.”

Which stat applies depends on what action you take and your action has to trigger the move. That means you can’t Defy Danger from a steep and icy floor with a charming smile just so you can use Cha, since charmingly smiling at the icy floor does nothing to it. On the other hand, making a huge leap over the ice would be Str, placing your feet carefully would be Dex, and so on. Make the move to get the results.

(Also check out Jeremy Strandberg’s re-engineered move for Homebrew World.)

Perhaps inspired by Defy Danger, the DW hack World of Dungeons has one move:

Rolling the Dice

When you attempt something risky, sum 2d6 and add one of your attribute scores, based on the action you’re taking. (The GM will tell you some of the possible consequences before you roll, so you can decide if it’s worth the risk or if you want to revise your action.)

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. And a total of 12 or more is a critical success; you do it perfectly to some extra benefit or advantage.

Skills: If you have an applicable skill, you can’t miss. A roll of 6 or less counts as a partial success, but with a bigger compromise or complication than a 7-9 result.

One of my concerns with Defy Danger is that players will sometimes meta-game and try to describe an approach that leverages their best stat rather than a fictionally appropriate approach. I’ve been playtesting a new default/catch-all/fallback move that doesn’t take any stat, so you just roll 2d6 and don’t add anything. Since this is for when you can’t remember the right move or can’t find an appropriate move, I want it to usually have slightly worse odds than using a more specific move. That said, I’m not willing to go all the way and make it 2d6-1 (to match the one stat a player starts with at -1).

So You’re Saying There’s a Chance

When as a group you can’t agree which move applies, but agree that success is possible but not certain, brainstorm what could go wrong. Roll 2d6. On a 10+, everything goes right, nothing goes wrong. On a 7-9, whoever rolled picks what went wrong from the group’s suggestions. On a 6-, the GM picks one or two things that go wrong.

Source: Yet Another Fantasy PbtA Hack

I think the ultimate inspiration for this mechanic was from reading The Ultimate Micro-RPG Book.

Right now I’m using this move in Impulse Drive, which my players feel like lacks a good selection of basic moves. They say that we fall back too much on Act Quick (the game’s take on Defy Danger, but using only one stat).

PbtA games, by design, are meant to accommodate imperfect play, where—in the heat of the moment—the right move from the “moveosphere” escapes the table. A good catch-all move makes this even easier.

Photo by Alexander Lyashkov on Unsplash. Updated on 2023-11-26 with the Basic Rule from Spirit of 77.