# 泥潭三 / 《終極魔界》 / Ultimate Demon Realm (nitan_san)

> slug: `nitan_san` · browser status: `playable` · native port: `40055`

The true 'third generation' release of the NT/nitan/Lonely engine lineage — its login banner literally reads 'once you enter the Mire, it runs as deep as the sea.' Like its close relative nitan_ceshi, it's branded in-game as 'Ultimate Demon Realm,' a skin over the shared nitan engine. A direct file-level comparison shows the two are near-total duplicates of the same authored world rather than independently evolved games: about 98% of matching-path files under d/ — the same Central-Plains cities, the same Five Great Sects, the same frontier zones — are byte-identical, while the two diverge much more in their engine layers (kungfu skills, commands, admin daemons each differ in roughly a third of files), pointing to separate later snapshots of one shared codebase. Character creation follows the same creation-myth path: choose a name and personality, reroll stats, and be delivered into the world by Pangu at the Valley of Life. It shares its sibling's independence from any external database — registration and saves are entirely local-file-based. A separate git-hosted mirror of this exact codebase is also in this collection as nitan3, confirmed byte-identical across 15,235 of 15,236 shared files and marked as a duplicate of this entry.

## Play in the browser (WebAssembly)

- Landing page (description + notes): https://mudlibs.fluffos.info/nitan_san/
- Play now (boots the WASM driver): https://mudlibs.fluffos.info/nitan_san/play.html

## Download source ZIP

- Same-origin ZIP (trimmed source tree, no need to clone the whole repo):
  https://mudlibs.fluffos.info/nitan_san/nitan_san.zip
- GitHub tree: https://github.com/fluffos/mudlibs/tree/main/libs/nitan_san
- README: https://github.com/fluffos/mudlibs/blob/main/libs/nitan_san/README.md
- Restoration notes (NOTES.md): https://github.com/fluffos/mudlibs/blob/main/libs/nitan_san/NOTES.md

## Run natively with FluffOS

1. Build a current FluffOS driver from https://github.com/fluffos/fluffos
   (native `build` / `build-debug`; see that repo's docs).
2. Download and unzip `nitan_san.zip` from the URL above (or clone
   `https://github.com/fluffos/mudlibs` and use `libs/nitan_san/`).
3. From the unzipped lib directory, ensure `config.fluffos` points
   `mudlib directory` at this tree (the checked-in file may contain a
   maintainer-local absolute path — edit it to your extract path).
4. Start the driver:

```bash
/path/to/fluffos/build/src/driver config.fluffos
```

5. Connect a UTF-8 MUD client to `127.0.0.1:40055`.

- Admin / wizard login: `fluffos` / `Mud@2026`
- If you host this on a public network, change the published default
  admin password before opening the port.

## Machine-readable catalog

- Site-wide catalog: https://mudlibs.fluffos.info/games.json
- Site-wide LLM overview: https://mudlibs.fluffos.info/llms.txt
- This file: https://mudlibs.fluffos.info/nitan_san/llms.txt