No matter how inactive my blog, I have been trying to come up with something for the One Page contest every year since 2013. This year I was going to post another suite of rooms from my megadungeon but inspiration struck at the last moment - "what if you had a dungeon that was inside a door? A giant door?" The rest practically wrote itself thanks to a very detailed engraving of a crunchy old-time castle door, some pun-generated monsters, and a meta-puzzle about opening the Door from within and who might want you to do that.
"Shrunken adventurers" is a trope verging on cliche so I gave the GM the chance to make the door an actual, 300' high door in some unfathomable dungeon, which I think is the clutch choice for sure. Anyway, it feels good to be able to throw something into the ring on fairly short notice!