This is a one-page (ish) dungeon for Dungeon World that leads with some lovely graphic design, and manages to pack a ton of atmosphere and flavor into its tiny space.
It's also got some ridiculously neat dungeon mechanics, a potent bit of horror, and is 100% worth dropping on a starting party for the wtf factor alone.
It doesn't necessarily have any treasure, so especially if you're converting it to something non-DW you might need to add your own, but I would thoroughly recommend this to anyone looking for a low-level adventure or medium-level sidequest for their preferred fantasy adventure game.