The core player mechanic in Dungeon World is a Move. A Move tell you the conditions required to make the Move (the Trigger), modifiers to your roll (usually an Ability Score modifier), and the specific results on Full Success (“You do it with little trouble”) or Partial Success (“You do it, but with complications or trouble.”). You get a Full Success when you roll 10 or higher on 2d6 (plus your modifier). Without any modifier’s, that’s roughly a 17% chance. You get a Partial Success on a 7 through a 9 on 2d6 (plus your modifier). Without modifiers, that’s roughly a 42% chance.

If your total is 6 or lower, that’s officially called “A Miss”. The player Moves don’t identify what happens on a Miss. GM Moves, however, give you a list of options, up do and including inflicting damage on the character. Notably, GM Moves don’t involve rolling dice yourself. NPCs and Monsters get GM Moves, not Player Moves. So that’s asymmetric play right there.

There are a couple different ways the game encourages narrative play rather than simulationist play, but that’s certainly the one that players and GMs are universally going to run up against first. And to expand on the “rolling the dice” bit, with one exception, the GM is encouraged to never touch the dice themselves. Technically, the GM is frequently encouraged to never touch the dice themselves, but there’s a glaring exception in the Monsters chapter, and it’s probably not what you think.

Well, it’s not what you think if you’re thinking “Hit Points”, which Monsters do have¹. No, there’s a random treasure table. Every goblin is tough as every other goblin (mostly), but every goblin is likely to have individualized treasure.

1. But initial Hit Points are static across monster templates. Got 10 goblins? You don’t roll 1d4 (or whatever) ten times to see how tough each one is. They each have 3 hit points to start².
2. Oh, and also, when a / the goblin(s) damage a character? The Player rolls the damage their character takes.