#RPGADAY: Favorite Game System

I'm going with Powered by the Apocalypse, because even though I haven't actually played Apocalypse World, I have played Dungeon World (and even written a bunch of content for it), and the whole "ask questions, use answers", "draw maps, leave blanks", and front development in general syncs up really well with my low-prep, wing-almost-everything, roll with the players' punches/actions style of running games.

Not only that, but the mechanics behind the system are very simple to learn, and plays quickly, smoothly, and flexibly: you declare what you want to do, and the MC/GM has you "make a move". All moves are handled by rolling 2d6 and adding some other modifier (usually in the -1 to +2 range): a 6 or less is a "miss", a 7-9 is a "weak hit", and a 10 or higher is a "strong hit".

That's it.

Every move tells you what happens on a 7 or higher (though you often make choices in the 7-9 range). For example, in Dungeon World when you Hack and Slash something, you roll+STR. If you get a 7-9 then you deal your damage to the target, and it makes an attack against you. If you get a 10 then good for you: you just deal your damage, though you can opt to deal an extra 1d6 damage if you want to take a hit, anyway. If you miss? Well...

Some moves tell you what happens on a miss, but a lot are left up to the MC/GM to suss out (or tell you what happens, in addition to whatever else the GM tacks on). I love the bit in Apocalypse World where it tells you to tell the players "on a miss, I'll tell you what happens", and then follows up with "...and I promise you won't like it". This is not only great for flexible outcomes, but also adds an element of uncertainty (especially since, as Dan will tell you, not all GM's dish out hard moves equally).

For example if you are trying to hack away at an ogre and roll a miss, you might just take damage, get your weapon knocked away, or have your shield smashed to bits. It might even be a combination of those, or the GM might make you choose between losing some hit points or losing your shield. You could also get a broken arm. Adventuring is unpredictably dangerous.

I dig how classes/playbooks are setup, especially coming away from the whole 5th Edition "playtest". They're collections of thematic moves to be sure, but they all fit on a single double-sided sheet of paper. Whatever you want to play, you grab a sheet, check some boxes, and you're good to go. When you level up, check a new move, and that's it: it's fast and allows for a good deal of customization since there are "officially" only 10 levels in the game, but about twice as many moves to choose from.

Thanks to Powered by the Apocalypse that's actually in a nutshell how I would describe Dungeon World: it not only does what I think 5th Edition Dungeons & Dragons wanted to do, but it does it better, simple, and faster: game prep and character generation is a snap, there is an incentive to play in character and build backstory between other characters, and since not everything is explicitly spelled out you get a more "old-school" vibe, just without all the kludgy legacy mechanics (even the pseudo-Vancian magic isn't so pseudo!).