Criticals?

Why aren't they a part of the game? and what does adding them in do, good or ill?

Considering what the game seems to going for, seems like something worth looking at (for my group atleast). Just wondering what the general feeling on the matter was.

They are part of the game, in a way. Certain classes have advanced moves that modify a basic move on a 12+ (Barbarians and Thieves have one for Defy Danger, Fighters have one for Hack and Slash). The reason every move doesn't have something written out for a 12+ is that it complicates move creation (what's better than a total success?) and it cheapens it for those players who picked up the advanced move.

Criticals: I look at critical failure this way: the riskier your action, the more it goes bad when you fail.

So you think it would be a bad idea to have a snake eyes prompting a hard(er) move be codified in the mechanics? I have a feeling I would occasionally just do that without thinking about it anyway, and having it spelled out means players can see it coming.

I see the validity in concern that it cheapens advanced moves, but a 12+ is somewhat easier than a 'natural' 12, especially for say a barbarian rolling with appetite on a maxed stat. And it doesn't need to be anything game altering. Those 12+ add extra effects, a crit could optimise. A move get's you to roll your damage die? It's auto maxed (or some varient), that's easy. Thinking about it now, it tends to disrupt my flow within the narrative going from 'Awesome! I rolled the best roll I possibly could' to 'but I fluffed the damage roll and it plinked of his armour' but maybe that's just me. Could be a downside I'm missing.

Things like Discern Realities are definitely harder, maybe the GM answers what they consider to be the most appropriate question from the list? I don't know, maybe the lack of follow up roll makes them less useful here, but I'm sure people could come up with something.

Dungeon World seems to me to be trying emulate old school dungeon crawlers, or atleast the stories that came out of that without all the (what some people condsider) unneccesary mechanical complexity that people usually leave out of said stories, holding up the action. That's why I assume we have this odd mix of strictly defined classes and roles, but very loose core mechanics. Nobody general cares or remembers what was rolled when they hit the ogre in the face with a club, unless it was a critical. The cheer goes up, and max damage or whatever is dealt. I think that aspect of the fiction is worth preserving. I geuss that's where people may disagree, on whether you think Dungeon World is about the fiction of a fantasy adventure story or a fantasy adventure gaming story.

Things don't have that many hit points as it is. But if you want to add it, it's just a custom move away.