Besides the genre differences and the setting differences implied by the genres, there’s one major difference between these two games: in Dungeon World you don’t get to use the moves against the other players. Sure you can attack them, but I don’t think that’s meant to be a key to the game. On the other hand, in Apocalypse World, the moves are written in such a way that you can clearly and freely use them against the other player characters.
The way Dungeon World handles the intra-party relationships – and thus conflicts – is actually quite elegant and definitely has its own strengths, however I do enjoy how Apocalypse World brings the intra-party conflicts to the forefront.
In Dungeon World, the relationships between PCs are a list of bonds. You get experience at the end of session if you and the other party consider one of them resolved. This is quite a beautiful system. Its very simple, it brings depth to the relationships, you have an incentive to pursue them, but you won’t get bogged down in one relationship, and those relationships always move forwards, because once you resolve a bond, you get another one.
Admittedly some of the bonds the characters start with probably have a tendency to take the relationships into certain directions (for example, the Thief has ‘I stole something from…’, which doesn’t necessarily have a lot of room to work with), but since you don’t have to act these out, but can just drop them if needed, this is not a real problem, as long as you don’t feel obligated to work everything out. You can just come to the conclusion that this isn’t something we want to pursue and if the other party agrees, mark down experience and replace it.
In Apocalypse World, relationships are represented by Hx, which ranges from -4 to +4. Any time you reach the lower or upper end of the scale, the Hx moves to -1 or +1 and you mark down experience. These are dependant on the other players. At the end of each session, each player makes a call on who knows his or her character better based on what happened during the session and that character then receives the +1 to Hx. This encourages people to interact, but since the relationships are very abstract on paper, this leaves a lot of room on how the PCs interact.
However, the moves bring their own flavor. Since you get experience from using stats, you are encouraged to use moves. This combined with the incentive to interact with other players means that those moves are often used on other players. Since those moves don’t generally include hugs and/or kisses, the relationships between PCs are usually quite strained, or they are outright enemies. And with the right group, that’s great, especially if despite the strained relationships, they have to work together for one reason or another.
Maybe in four or five years I’m going to be completely behind some other system or engine, but right now I feel the AW Engine is just great. It seems to bend to your needs. All the systems I’ve played are great, in huge part because the engine allows for these hacks which bring totally different feel to the games.
Of course, AW doesn’t have be about intra-party conflicts. Vincent Baker said as much at Ropecon: he sees the game more like Firefly, where the crew is conflicted but ultimately stays together. However, it’s our game, not his – especially since he made the “dick move” of writing it ambiguously and using really violent examples of intra-party conflicts – but I think the rules themselves actually do not take the game to the direction you said it would.
Our game was more like an HBO show, not Firefly, but I don’t think it was merely the rules. Sure, the highlighted moves enforced it; but I think it all began with our (or my) interpretation and communication of what the game is about. I pitched it as an HBO show, which primed everyone’s expectations. The characters were at each other’s throats to begin with and I thought my external threats were lackadaisical. Things snowballed and it very much became a PvP game.
But with a strong community, threatened by a clear external threat (or one from within the community but that the characters all oppose), and a lot of NPCs, things wouldn’t necessarily move so heavily into PvP territory.
It doesn’t have to be PvP, but due to the nature of the moves, the relationships will definitely be strained. Also, since I’m a big proponent of using the right tool for the right job, I don’t think trying to go too much into another direction is necessarily a good idea either.