For The Dungeon is a short, high-energy, light-hearted rpg about minions defending a dungeon from adventurers. It's multiplayer, easy to learn, and maybe the perfect intro to indie games if you're used to DnD and want to try something different for a one-shot.
The PDF is 47 pages, all pretty short and easy to read, and it's got great layout and illustrations---although in a few places they feel a little formatted for print, and pictures fall partly off of one page and onto another.
The core mechanics are simple---you roll d6s and try to hit at least one 4 or higher---and complications are one of the most common results, giving the game a sort of balance towards chaos.
Character creation is nice and crunchy, though, and gives you lots of options to manipulate the dice results through your Perks. Anything from boosting the dice on a specific type of Move (basically, what would be a skill in D20) to flipping a critical failure into a critical success once per session is available for players to pick up.
There's also a nice downtime system, for getting benefits and recovering resources between adventures.
There is no bestiary, which I think would have been a nice touch, but monster creation is *really* easy for GMs, and there's both plenty of solid GMing advice and all the toolkit you need for throwing together monsters included in the book.
Overall, if you're looking for a zany one-shot or slightly more serious dungeonpunk campaign, and if you like great art and a light-but-chaotic atmosphere, get this.