Dungeon World, by Sage LaTorra and Adam Koebel, is a tabletop role-playing game that focuses on storytelling and ease of use. One game master and 3-5 players collaborate to tell a low fantasy story. Anyone who has played some flavor of Dungeons & Dragons (aka DnD), or really any RPG, will recognize most of the tropes but the system is highly streamlined.
Character sheets are simple, with 1 to 2 pages containing all information so the players don’t have to refer back to the book. There is no skill list, all players instead sharing a list of common moves that use their attributes without training modifiers. All outcomes are determined by rolling 2d6 as opposed to a d20, with an added wrinkle- only the players roll for actions. Players failing a roll is the main opportunity for the opposition to make moves, and also the main generator of experience. It creates an interesting and spontaneous game, where the players are the primary movers of events. Failed rolls giving experience also acts as a good equalizer and takes some of the sting out of failure. Dungeon World emphasizes failing forwards, so the story keeps evolving instead of coming to a grinding halt when a roll fails.
The downside is that the GM needs to be very comfortable adjusting scenes and encounters on the fly or simply making them up as they go along. Collaborative world building is encouraged, but in my experience players react poorly to being put on the spot- if they offer something it can be integrated but the bulk still falls on the game master. The game master’s section offers some excellent instructions on this and running a game in general but you still need to be comfortable improvising.
In the same vein, combat is much simpler than in most games- no battle mat required, which helps keep things fast. Hit point pools are small so things don’t drag on. This makes things more lethal for the players as well but the simplicity of the rules makes it simple to adjust encounters on the fly. There is no recommended monster budget for encounters as in DnD, in part because not all the classes are balanced for combat- the game master will need to create situations where the more utility focused classes shine, assuming they are being played.
Conversely, if you are coming from another Powered by the Apocalypse Game, Dungeon World will have longer and less lethal combat than you are used to.
Something to be aware of with the system is how quick the leveling is; not a problem itself but players start to gain access to game-breaking abilities around level 7 or 8, which can quite easily be reached in 10 sessions. At this point players will be able to one shot even the toughest monsters in the book, teleport unlimited distances, succeed on most roles involving their main attribute, and in general trivialize any challenge thrown their way. You’ll need to plan campaigns to end at or shortly after 10 sessions to keep power creep from making things boring. I just wrapped up a 13 session campaign and my players dealt with the worst the book had to offer without too much difficulty.
The games themselves are also shorter- I’ve always tried to keep my sessions to four hours, as have most of the people I’ve played with. Pathfinder and DnD always strained against this, especially 4th edition DnD, where you can really only do one combat encounter in a session. Dungeon World’s simpler rules let you run numerous combats in a session with plenty of time for exploring and character development as well, something I love about the system but people who enjoy tactical combat may not. There is also no set initiative- I tried to give everyone turns and only making GM moves on failed rolls but ended up having to play a little loose and fast with the monster’s actions to keep things interesting
Price wise its no contest, $10 for a Dungeon World PDF, or twice that for the paperback, which includes all the playbooks and, gamemaster material, and bestiary, vs at least $30 for even a player’s handbook for more popular systems, and you need several hardback books to run 5th edition DnD. Obviously if you pirate the books this isn’t an issue, which is a fairly common practice in the RPG community, but I like having books to hold and they aren’t much cheaper used.
TL,DR: A light on rules & story focused system. Ideal for newer players but the game master needs to be able to improvise. The price is right so give it a try if it sounds interesting to you.