I'm rebuilding the Metin2 server (TMP4) in Rust – here's where I am

[Matamune 3]

Hi everyone!

I'd like to share a project I'm working on: a complete rewrite of the TMP4 game server in the Rust programming language.

 

What is this, in simple words?

A Metin2 private server has two parts:

The client: the game you launch on your PC.

The server: the program that handles accounts, monsters, fights, items, quests and saving your character.

TMP4 is a well-known server base written in C++. I'm rewriting that server in Rust, a modern and safer language.

Same client: you keep the normal, unmodified TMP4 client and play as usual.

Same data: maps, quests, items, monsters and the MySQL database all come from TMP4.

Same behaviour: every system is copied from the original TMP4 code, with the same formulas, drops and messages.

The goal is to reach 100% of what TMP4 does first, then improve from there.

 

TMP4 vs Rust: stability and security

 

Bad packets sent by cheaters

TMP4: a badly formed packet can crash the server

Rust: every packet is checked. All 55 client packet types were tested with random garbage, and nothing crashed.

 

Memory bugs (a classic source of crashes and exploits)

TMP4: possible anywhere in the code, and compiler warnings are turned off

Rust: impossible by design. Only 4 small "unsafe" spots exist, all in the Lua quest bridge.

 

Database hacking (SQL injection)

TMP4: about 30 database queries are built by hand from text

Rust: every query is protected automatically

Passwords

TMP4: old MySQL hashing

Rust: modern hashing (argon2)

 

A bug during one player's action

TMP4: can take the whole server down

Rust: only that player is disconnected, and everyone else keeps playing

 

Item duplication when saving

TMP4: depends on a separate cache program

Rust: every item keeps a fixed ID, and saves stay safe even when many players log out at once (0 errors in my tests)

 

Where it runs

TMP4: FreeBSD only, 32 bits, so 4 GB of memory at most

Rust: Windows and Linux, 64 bits

 

How to build it

TMP4: complex Makefiles and old libraries

Rust: one command, cargo build

 

 

Is it fast?

I tested it with 500 fake players (bots) on one PC with a Ryzen 9 (8 cores). The server, the database and the bots all ran on that same PC.

I made the test hard on purpose: around 250 players packed into each starting village, all walking, attacking and chatting at the same time.

11 ms reaction time for 95% of actions (anything under 50 ms feels instant)

29 ms at worst

About 300 MB of memory used

0 disconnects or errors

1.6 seconds to start with all 65 maps and ~52,000 monsters

7.5 ms to save a character with 100 items 

To be honest: I couldn't run the original TMP4 on the same PC, because it needs 32-bit FreeBSD. So there is no measured speed comparison yet. A fair side-by-side test on the same hardware is planned.

 

What already works?

done · partly done · not yet

 

Login and characters

Login, character creation / deletion / rename, empire choice

Guild emblems (upload and display)

 

The world

All 65 maps, walls, safe zones in towns, portals

All monster spawns (~52,000 monsters)

Monsters chase you and use skills

Archers and mages attack from range

Bosses have their special abilities

Dungeons: flame dungeon, catacombs, devil tower, spider queen, heaven's cave…

 

Quests

All 237 TMP4 quests work, from the tutorial to the level 99+ story

Your character

Stats, all bonuses, buffs, level-up, exp

All 77 skills, including training up to Perfect Master

PvP duels, PK mode, alignment

Polymorph (marbles), horse (visible, feed it, ride it), pets

 

Items

Inventory with real item sizes, belt inventory

Drops, upgrades +0 to +9, bonuses up to 7, stones in sockets

NPC shops, your own private shop, trading, storage, item mall

Crafting (cube), full Dragon Soul, fishing, mining

 

Playing with others

Party with exp sharing and roles

Guild ranks, skills and exp donations

Guild wars with scores, spectators and bets

Guild land and buildings

Friends list, private messages, shout

Marriage: engagement, wedding ceremony, couple bonuses

 

Events

GM event flags (bonus exp / drop / gold)

Event drops (Halloween, Easter, Christmas…)

OX quiz, duel arena, three-kingdoms war

Castle siege, Blue Dragon boss

Monarch (emperor) system: written, being integrated and tested

 

Server administration

GM commands: the main ones work, some specialised ones are still missing

Full action logs (gold, item and login history)

Account and IP bans

All of TMP4's configuration options

Multi-channel: each channel is separate for now, so you can't whisper a friend on another channel yet

 

How do I know it works?

About 2,100 automatic tests

Many of them simulate real players connecting with the real TMP4 data: dungeons, weddings, guild wars, fishing, trading, logging out and back in

Every change must pass all of them before it goes in

 

What's next?

Finish integrating the monarch system

Remaining GM commands, logs, bans and config options

Multi-channel

A fair speed comparison against TMP4 on the same PC

An open test with real players

Questions, ideas and feedback are very welcome, especially if you know TMP4's weird little behaviours!

Edited September 28 by Matamune
edit space

[friendtm 4]

Do you intend on sharing this? Maybe a git repo? Not that i will use this but i find this interesting and im a little curious, at least i'd like to check it.

[Matamune 3]

i think share it yes idk how for now if git or other thing 

[Macromango 30]

This is a grat idea i would collaborate on that when public

[Matamune 3]

Update i add a complete web dashboard for the serverfiles with some nocode feature for make quest and "plugin"

What's in it: Operations • Dashboard: live stats per channel (players online per map and empire, tick times, queue depth), with graphs. • Players: search, kick, temp or permanent bans with a reason, and an inventory viewer that works even when they're offline. • Announcements: to all channels or a single map. • Plugins: status per channel, perf per event, enable, disable, reload, deploy and uninstall. There's also a "Test" mode that simulates an event without actually giving anything to anyone. • Event flags manager. Content creation (no-code) • Quest editor: opens all the existing TMP4 quests and saves them back byte-for-byte identical when you don't change anything. • Two views: Cards, where each line reads as plain English-style sentences for beginners, and a Blueprint node graph like Unreal. • Plus diff, history, a state graph and a dialogue preview. • It warns you when another quest or plugin already reacts to the same event, for example "this mob already drops that item in quest X". • Plugin editor: same Cards/Blueprint approach. It generates Lua plugins with hot reload, and comes with templates like a world boss, daily login rewards, weekend double drop and an /online command. Game data (inspired by metin2.tools, but wired to the live server) • Proto editor: items and mobs, with real icons, filters, bulk edit and TXT/SQL import/export. • Drops and chests: mob_drop_item, common drops and special_item_group, showing the real drop %. It can also answer "who gives this item?" and run a loot simulator. • NPC shops: shown in the real in-game 5×8 window with icons. • Regen editor: spawn zones drawn on the real map images pulled from the client packs, drag and resize with the mouse, with live mobs and players shown on top. • Damage calculator: uses the server's actual combat code, not a reimplementation, and can compare two builds step by step. • PNG → TGA icon converter. • Client assets: reads the client's .eix/.epk packs directly to extract maps, item and skill icons. Every change is validated, versioned (history and rollback) and hot-reloaded on every channel, so no restart is needed.

[friendtm 4]

On 10/2/2026 at 5:41 AM, Matamune said:

Update i add a complete web dashboard for the serverfiles with some nocode feature for make quest and "plugin"

What's in it: Operations • Dashboard: live stats per channel (players online per map and empire, tick times, queue depth), with graphs. • Players: search, kick, temp or permanent bans with a reason, and an inventory viewer that works even when they're offline. • Announcements: to all channels or a single map. • Plugins: status per channel, perf per event, enable, disable, reload, deploy and uninstall. There's also a "Test" mode that simulates an event without actually giving anything to anyone. • Event flags manager. Content creation (no-code) • Quest editor: opens all the existing TMP4 quests and saves them back byte-for-byte identical when you don't change anything. • Two views: Cards, where each line reads as plain English-style sentences for beginners, and a Blueprint node graph like Unreal. • Plus diff, history, a state graph and a dialogue preview. • It warns you when another quest or plugin already reacts to the same event, for example "this mob already drops that item in quest X". • Plugin editor: same Cards/Blueprint approach. It generates Lua plugins with hot reload, and comes with templates like a world boss, daily login rewards, weekend double drop and an /online command. Game data (inspired by metin2.tools, but wired to the live server) • Proto editor: items and mobs, with real icons, filters, bulk edit and TXT/SQL import/export. • Drops and chests: mob_drop_item, common drops and special_item_group, showing the real drop %. It can also answer "who gives this item?" and run a loot simulator. • NPC shops: shown in the real in-game 5×8 window with icons. • Regen editor: spawn zones drawn on the real map images pulled from the client packs, drag and resize with the mouse, with live mobs and players shown on top. • Damage calculator: uses the server's actual combat code, not a reimplementation, and can compare two builds step by step. • PNG → TGA icon converter. • Client assets: reads the client's .eix/.epk packs directly to extract maps, item and skill icons. Every change is validated, versioned (history and rollback) and hot-reloaded on every channel, so no restart is needed.

What API are you using for the dashboard live stats?
Those functions on a dashboard are useful stuff.

[Matamune 3]

On 10/6/2026 at 11:39 AM, friendtm said:

What API are you using for the dashboard live stats?
Those functions on a dashboard are useful stuff.

 No external API, it's all homemade. Each game channel exposes its own stats (players, per map, tick time, memory) on a local-only JSON port. The admin panel polls every channel every 5 s, keeps a short history, and the dashboard page fetches that from the panel's /api/metrics on a timer. No websocket, no third-party service.