I recently had the opportunity to run
Gullet of the Rust Demon, written by Dan D. of the blog Throne of Salt. I ran it using Ashes Without Number, placing it in a preexisting sandbox. This dungeon first struck me because of its unusual map and its only monster, The Ooze. An indestructible mass of flesh and bone, it retreats after taking 1d20 damage, rerolled every encounter. The first room of the dungeon is an atrium with 6 doors leading away from it, and bizarre statue of "a tangled, tortured mass of humans" with a bottomless hole. The statues features imply some sort of explanation to the Ooze, although the dungeon itself doesn't provide anything to this end. Each room contains oddly specific contents that also imply some incomprehensible purpose to this location, rather than giving it away, each room really just piles more questions on top. Room 6 is a personal chamber/prison cell with "I am feeling ill" written on the wall. This room in particular is an opportunity to present an answer, is the Ooze maybe the person who was here, a final cultist of some sort maybe, and his curse led him to crawl into the bottomless hole under the statue, turning him into the cursed Ooze that haunts this ruin? We'll never know, but anyone who runs it will interpret it in their own way. While I realize this open ended-ness is an invitation to be creative, I think more fleshed out lore would make it a more satisfying adventure to run.
The primary conceit of Gullet of the Rust Demon is that it is an escape room style dungeon. After entering, the doors slam shut behind you, and you have to solve the puzzle of the dungeon to escape. My players, being paranoid dungeon-heads, searched the entrance to the dungeon, and discovered evidence of the trap door and managed to circumvent the trap with a chopped down tree from nearby. This didn't affect the experience too much. They still explored the dungeon, looting and pressing their luck with the Ooze, until they decided to call it and came out with a fair bit of technological salvage. The exploration of the central atrium and its surrounding rooms punctuated by Ooze attacks was a very different kind of dungeon crawl, especially because the party had a clear escape route through the front gate propped open by a tree trunk as an option. I thought the mechanics of the dungeons design created awesome tension for the delve. Ultimately the origin or purpose of the Ooze was not important, and the players got their treasure. If I ran it again, I would want some motivation for the Ooze, so that escaping the dungeon isn't the only puzzle. Lets say the Ooze was the last living cultist, who gave their body over to their evil god as a way to continue to exist after it lost the faith of its cult. The Ooze will attack any who violate its sanctum, but in fact more than anything it wants to be worshipped once again.
