Mystic Nights (PS2) Multiplayer Private Server

This is an Open-Source Private Server for the Playstation 2 video game Mystic Nights, written in Python and reverse-engineered from the client binaries.

Mystic Nights (미스틱 나이츠) is an obscure Korean-Exclusive survival horror Playstation 2 title. It was developed by N-LOG Soft and published by Sony Computer Entertainment Korea in 2005. Although a North-American release was planned, the game was never localized.

This project's goal is to revive the Online Multiplayer functionality of the game by reverse-engineering the expected packet replies required from the server. This is achieved through examination of the client side packet parsing code through Ghidra decompilation (MIPS 5900 to C), analysis of values at target memory addresses in EE and IOP RAM (using PCSX2 Debugger) during different game states and some careful packet fuzzing.

If you like my work, feel free to show your support: https://ko-fi.com/jeremydecola

I'm hosting my server for a limited time!

For more information check out : https://jeremydecola.github.io/Mystic-Nights-Archive/multiplayer.html

Connect to an Existing server

Patch the Mystic Nights iso with my latest English Translation patch: https://github.com/jeremydecola/Mystic-Nights-Translation/tree/master

1. PCSX2/DEV9 Setup (for Online Play)

• PCSX2 emulator (PCSX2.net) with DEV9 network plugin.
• Open the "Network & HDD" menu in PCSX2. Make sure Ethernet is enabled. Select Ethernet Device Type: Sockets or PCAP Bridged. Then, select the name of the adapter you use to access the internet. (Something like "Ethernet").

2. Patch the Mystic Nights ISO so that it connects to the Private Server

1. Find the IP address of the server you want to connect to.
2. Patch Mystic Nights ISO with server IP address (use the provided patch_ip.py).

• IMPORTANT: The patch_ip.py tool doesn't work with the original untranslated Mystic Nights iso. If you would like to use that one, you will have to hex edit the IP address manually.
• Note: My latest v1.2 translation patch already patches the IP address to the PUBLIC IP of my server.

3. Set up Network Configuration on PS2 Memory Card.

1. Boot up Mystic Nights in PCSX2 and Navigate to NETWORK GAME from the main menu.
2. Follow the guide on the Mystic Nights Archive website: https://jeremydecola.github.io/Mystic-Nights-Archive/multiplayer.html

Host the server yourself

Prerequisites

Patch the Mystic Nights iso with my latest English Translation patch: https://github.com/jeremydecola/Mystic-Nights-Translation/tree/master

1. Python Environment

• Python 3.9+
  Download Python

2. Database (Choose One)

• SQLite 3 (Default — easy, local, no setup required)
• PostgreSQL 13+ (Advanced/production, optional)

3. Python Libraries

Install required Python packages:

pip install asyncpg aiosqlite aioconsole

Or using requirements.txt:

pip install -r requirements.txt

Contents of requirements.txt:

asyncpg
aiosqlite
aioconsole

4.1 PCSX2/DEV9 Setup (for Online Play)

• PCSX2 emulator (PCSX2.net) with DEV9 network plugin.
• Open the "Network & HDD" menu in PCSX2. Make sure Ethernet is enabled. Select Ethernet Device Type: Sockets or PCAP Bridged. Then, select the name of the adapter you use to access the internet. (Something like "Ethernet").

4.2 PCSX2/DEV9 Setup (for Local Play)

• PCSX2 emulator (PCSX2.net) with DEV9 network plugin.
• Create a TAP network adapter:
  • Windows: Install OpenVPN or TAP-Windows driver
  • Linux: sudo apt install uml-utilities and create a tap device using tunctl or ip tuntap
• See PCSX2 DEV9 Setup Guide for bridging instructions.
• Open the "Network & HDD" menu in PCSX2. Make sure Ethernet is enabled. Select Ethernet Device Type: TAP. Then, select the TAP adapter that you created.

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Instructions (Windows & Linux)

A. Server Setup

1. Clone or Download the Project

git clone https://github.com/jeremydecola/Mystic-Nights-Private-Server.git
cd Mystic-Nights-Private-Server

2. Database Configuration

SQLite (Default, easiest):

• No manual setup needed.
• On first launch, mysticnights.db is created automatically and schema loaded from mn_sqlite_schema.sql.
• (Optional) To specify a custom database file, set the SQLITE_FILE environment variable.

PostgreSQL (Advanced/Production):

1. Create a PostgreSQL database and user.
2. Import the schema:

   psql -U youruser -d yourdb -f mn_postgres_schema.sql
   

3. Set environment variables as described below.

SUPER IMPORTANT

The DATABASE contains a SERVERS table which holds the IP address of the 10 servers that are available to connect to. When you chose the first server in the list and try to log on, it then tries to establish a TCP session with the IP address associated to server 1. You must update the ip_address in the database to match your HOST (Server) IP.

3. Environment Variables

Set these before running the server (SQLite):

Variable	Description	Example
DB_TYPE	"sqlite" or "postgres"	DB_TYPE=sqlite
SQLITE_FILE	SQLite DB file name (opt)	SQLITE_FILE=mysticnights.db
SQLITE_SCHEMA	SQLite schema file (opt)	SQLITE_SCHEMA=mn_sqlite_schema.sql

Set these before running the server (PostgreSQL):

Variable	Description	Example
DB_TYPE	"sqlite" or "postgres"	DB_TYPE=postgres
PG_HOST	Postgres host	PG_HOST=localhost
PG_DBNAME	Postgres DB name	PG_DBNAME=mysticnights
PG_USER	Postgres username	PG_USER=postgres
PG_PASSWORD	Postgres password	PG_PASSWORD=secret

On Windows:
Set variables in Command Prompt for the current session:

set DB_TYPE=sqlite
set SQLITE_FILE=mysticnights.db

On Linux/macOS:

export DB_TYPE=sqlite
export SQLITE_FILE=mysticnights.db

4. Run the Server

python mn_server.py

• By default, the server listens on ports 18000 and 18001 (change in source if needed).
• Admin commands are available from the console after launch.
• The DEBUG variable can be used to print logs for troubleshooting purposes. Set the global variable DEBUG = 1 in the code. In production DEBUG should be set back to 0 as printing can be quite ressource intensive when we have multiple concurrent client connections.
• If you plan to host a server, you should probably run this as a service instead.

5. Connecting from PCSX2 (Gameplay)

1. Patch Mystic Nights ISO with server IP address (use the provided patch_ip.py).
2. Configure DEV9 plugin in PCSX2:
   • Exactly 1 PCSX2 client: Set up a TAP adapter and bind DEV9 to it in the "Network & HDD" menu of PCSX2. Modify the properties of the TAP adapter so that the IP address corresponds to the IP of the server that your games are trying to connect to (the IP that is hardcoded in the HOST global variable in the server code and the same IP that you patched in with patch_ip.py).
   • More than 1 PCSX2 client: Set up a unique TAP adapter for each PCSX2 instance you wish to run - bind each DEV9 of each PCSX2 instance to a different TAP adapter in the "Network & HDD" menu. Then, bridge your TAP adapters together. Example in Windows using Microsoft "Network Bridge". All of the TAP adapters can't have their IPv4 addresses changed once they're part of the "Network Bridge". Modify the properties of the "Network Bridge" so that the IP address corresponds to the IP of the server that your games are trying to connect to (the IP that is hardcoded in the HOST global variable in the server code and the same IP that you patched in with patch_ip.py).
3. Connect in-game: Use the Multiplayer/Online menu in Mystic Nights.

6. Server Usage

• Player registration, login, lobby creation/join, and game synchronization are all handled by the server.
• Disconnects, lobbies, and player stats (rank/score) are auto-managed in real-time.
• The admin console allows sending raw packets and shutting down gracefully.

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Limitations

• The DNAS Bypass only works once. If you exit NETWORK GAME or get logged out for whatever reason, reset your PCSX2 instance to get passed DNAS CHECK again.

Troubleshooting

• Do your IP addresses match everywhere?
  • The IP set in MN_SERVER.py - HOST global variable
  • The server IP in the .iso (run patch_ip.py)
  • ip_adress field in the database SERVERS table
• Firewall Issues:
  • Ensure inbound TCP traffic to ports 18000 and 18001 is allowed.
  • On Windows, allow PCSX2 and Python through your firewall.
  • On Linux, use ufw allow 18000:18001/tcp or equivalent.
• DEV9/TAP Adapter Not Working:
  • Ensure TAP adapter is enabled and bridged to your main connection.
  • Check PCSX2 logs for network plugin errors.
• Database Problems:
  • For SQLite: Ensure the folder is writable and mn_sqlite_schema.sql exists.
  • For PostgreSQL: Verify credentials and connectivity. Use psql to test login.
• Other Issues:
  • Run Python with elevated permissions if necessary (Windows: Run as Administrator; Linux: use sudo only if needed).
  • Set DEBUG=1 for verbose output (edit the mn_server.py source).

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License & Credits

• Reverse engineering, code, and server: Jeremy De Cola
• Translation patch: Jeremy De Cola
• Mystic Nights © N-Log Corporation, SCE Korea, 2005
• MIT License. Please don't forget to credit me when re-using my code.
• This project is non-commercial, for preservation/educational use only.

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Contact & Community

For questions, bug reports, or to join the project, open an issue or contact jeremydecola on GitHub.

*PROGRESS

1.0.0

Public release.

• Fixed 18000 session cleanup regression.
• Cleanup and improved README

0.9.12

• The server used a flag to blindly skip the first lobby join packet after a Quick Join, leading to unreliable behavior under high latency or packet reordering (sometimes skipping too many or too few join attempts).
  • When a player uses Quick Join, the randomly selected lobby index is now stored in the session.
  • The server will only accept lobby join packets matching the stored lobby index. All others are ignored while Quick Join is pending.
  • Once the correct join is processed, the pending state is cleared.
  • If no matching join arrives within 5 seconds, the server sends an explicit error packet to the client and clears the Quick Join state.
  • A new background coroutine (quick_join_timeout_watcher) handles these timeouts efficiently.
  • Even if Quick Join fails, we block/ignore lobby joins for 1 second since client attempts to blindly join lobby 0.
• Overriding print() function to return immediately if not DEBUG
  • Print statements are ressource intensive and are a bottleneck when trying to scale to hundreds of concurrent client connections.
• Removed CLIENT_GAMEPLAY_PORT from conditional checks for lobby broadcasts.
  • The client port is NOT always 3658. It varies greatly.
• Disconnecting other sessions with same player_id (targeting Connection Manager 18000 session) on Channel Join
  • Echo Watcher would cause disconnects o