Yeah, combat doesn't work that way in DW. The GM never rolls, only the players do. Here's something I wrote for another forum, explaining how combat works in Dungeon World:
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Dungeon World Combat For Total Beginners, pt 1------------------------------------------------------------
Dungeon World is an awesome game! It's the most fun I've had in years of gaming, partly because it rethinks all the rules behind a dungeoncrawl adventure. A lot of new GMs and players are confused by the way DW handles combat in particular, because it keeps the storygaming focus and doesn't break the action down into turns or rounds or whatever. I am by no means an expert, and I'm not affiliated in any way with the creators, I'm just a guy who has been running a really fun campaign and I want to share some things that I've learned, in hopes that other groups will pick up and understand this awesome, awesome game.
A lot of people are confused when they first see the *World games.
The GM doesn't roll dice, instead they "make Moves." One of their Moves is Deal Damage, does that mean that on their turn, the GM says, "Um, the orc hits you for 5 damage"? No, it doesn't. You're not being arbitrary here, it's just that the players' dice decide the outcomes of all your moves.
Here's how combat flows in Dungeon World, very simply:
1. You narrate the beginning of your NPC's action
2. The player responds to your action
3. If that response triggers a move (it usually does), the player rolls
4. You narrate the conclusion of the action, based on the player's reaction or result of their rolls
Here's an example:
GM:"The orc swings his club down at you. What do you do?"
PC:"I knock it aside with my warhammer and smash his skull!"
GM:"Sounds like we're doing some Hack & Slash, roll for it."
PC:"I got an 8, that's a partial success, yeah?"
GM:"Yeah, you knock the first blow aside, but he's relentless. You're both smashing each other and it's a full-on bloody brawl. We both roll damage for this."
So we're still
rolling when we encounter danger or chance, it's just that the
PCs are rolling the dice and you're interpreting the results. Combat actually runs really smoothly this way, and it doesn't feel like everyone is just taking turns hitting each other. Instead, it becomes a fluid back-and-forth.
Just remember that your job as the GM is to set up a dangerous situation, and call for a response from the players. Let the player's response determine the outcome of the situation that you set up."The goblin is lunging at you, what do you do?"
"Once the pillar breaks, the ceiling starts crumbling down above you, what do you do?"
"Those archers begin firing from across the clearing, arrows are whizzing by, what do you do?"
"The ogre raises his club up high, and starts swinging it down at you. What do you do?"
"You raise your shield in time. His hammer clangs against it and he just keeps swinging over and over. He's pummeling your shield, your arm is going numb but you're not injured. Suddenly, he swings low, aiming for your legs. What do you do?"After you determine the outcome of the player's response, it's the your turn to react again. So the you respond by setting up another dangerous situation, flowing from whatever just happened in the previous move. This will be obvious, usually, because it's the natural extension of whatever is happening in the game. The orc swings his club and the player decides to counterattack, now it's back to you: the orc probably swings again, or tries a different tactic like going for the PC's legs, or he lunges and tries to grapple the PC. Then the player will respond once more, maybe roll some dice, and then it's back to the GM.
Back-and-forth, setting up situations for each other and responding to them.