I'm not so sure. I find it good to know the NPC, even more so the important ones. They are 'set'. They don't just change on a whim.
But what is an example of this? You say that players can never alter game reality independent of the GM....but that is the ONLY way a GM and Player GM can "work together". Otherwise it is always "GM makes and controls everything always", and player can make a vague suggestion once in a while. And...maybe the GM will accept and use what the player says.
In Dungeon World the game itself is first described as (and I'm going to paraphrase instead of going to the trouble to cut and paste here) a game of adventure in a fantastic world where "you and your friends
are those heroes." You play to do amazing things, struggle together, and because the world still has so many places to explore. The heroes are explained to be basically D&D-esque fighter, ranger, paladin, wizard, etc. so its a pretty tight thematic space, basically about the same as D&D.
The play loop is simple, its a conversation. The GM says something, one or more players respond to that, the GM says something else, etc. There's no necessary preexisting fiction, its a 'story now' type game (although the GM is allowed to, even expected to, prep to a degree). That is, the GM will say where you are and what you see, and what's going on there, and then one or more players will respond on behalf of their PCs, stating what the PC does. If whatever the player says fulfills the trigger condition for a move, then that move happens. A move is just a 'package' of mechanics, sort of like a spell in D&D perhaps. If no move's trigger conditions are met, then the fiction simply advances. There are no 'out of character' mechanics in DW, though some mechanics could potentially be 'meta-game' in terms of how they work with mechanical game state. Either a player or the GM can always ask questions too.
Most PC moves trigger a throw of 2d6, with a 6 or less indicating that the GM says what happens next and you mark XP. On a 7-9 You do it (whatever action you stated you took) but with complications or trouble. On a 10+ you do it with little trouble. Specific moves may modify these three outcomes to a degree, but the numbers never change and the general results are always in line with above. Every move includes a +ABILITY (one of the 6 D&D ability score modifiers). For example if you described attacking a monster, you have made the Hack and Slash move, roll+STR (2d6 plus your Strength modifier). On a 10+ you deal damage and avoid your enemy's attack. On a 7-9 you both damage each other. It doesn't really say what a 6- result entails, the GM can literally say ANYTHING (though it must meet other general criteria, so not "you die horribly" unless that really is appropriate).
That's it, the other moves cover most of the sort of stuff your average adventurer is likely to do, and each class has a whole list of custom moves, like casting spells, or doing bonus damage, etc.
The GM doesn't really have specific moves, per se (although there are lists of GM moves, they're more like telling you stuff you CAN do, not a restricting list of what you must do). Instead the GM has an Agenda
- Portray a fantastic world
- Fill the character's lives with adventure
- Play to find out what happens
Accomplishing the agenda is achieved by following these principles
- Draw maps, leave blanks
- Address the characters, not the players
- Embrace the fantastic
- Make a move that follows
- Never speak the name of your move
- Give every monster life
- Name every person
- Ask questions and use the answers
- Be a fan of the characters
- Think dangerous
- Begin and end with the fiction
- Think off-screen, too
The GM makes a move when:
- Everyone looks to you to find out what happens
- the players give you a golden opportunity
- they roll a 6-
When the players are just looking to you to find out what happens, you make a soft move, otherwise a hard move. A soft move is one that puts pressure on the PCs, but doesn't cause any really irrevocable harm to them. A hard move brings badness, damage, loss, things get worse in a way that can't be fixed (at least in the short term). "You are lost" is a soft move, a character can get unlost, nothing bad has happened yet. "You fall in a pit and take 7 damage" is a hard move, direct badness. As an example: Joey goes running down the unmapped corridor, hoping to outrun the killer bees; golden opportunity - hard move, he falls in a pit and takes 7 damage. Yeah, he was in a tight spot, but careening down an unknown hallway in a dungeon is asking for trouble, and he got it!
But the point is, whenever the GM does something, says something, describes something, always the agenda is the reason for it, and the principles guide the execution of it. Sure, Joey fell in the pit and injured his leg, but the killer bees flew past him and he might get out alive (be a fan of the characters)!
This is the core of narrativist play, though certainly not the way all such games work. The GM looks at the situation, the characters, their wants, needs, desires, and the established fiction, and pushes things on, puts pressure on them, etc. If they manage to get their 10+'s well, maybe then they make things better, and if you are rolling 2d6+3 (the best modifier available) you got a pretty decent chance of success. Also there are things like 'forward', such as certain successful moves allow a player to get a bonus on a later roll. A smart player will play to the odds and try to trigger moves his PC is good at and get some forward to spend. So, with a bit of luck the characters can pull through, gain loot, gather equipment (more bonuses) and if they RP well and are successful, they get XP and advance in level.
Honestly, the main difference is the GM is not making everything up ahead, instead its mostly done on the fly as you go building up a crazy fantastical world filled with hair-raising danger and thrills!
