Private Servers (Game Decompilations & Reimplementations): open-source projects that exist because someone reverse engineered a closed product, sorted by GitHub stars.
World of Warcraft server emulator (MaNGOS fork)
Modular World of Warcraft 3.3.5a server emulator
Lightweight extensible Minecraft server in C++
Ragnarok Online server emulator in C++
Minecraft Bedrock server software built from scratch in PHP
Lightweight Minecraft Java server written from scratch without vanilla code
Rust framework for building Minecraft Java servers
Reimplementation of the Minecraft server in Rust
Open-source reimplementation of the Among Us game server
Open-source Minecraft Java server implementation
Open Tibia MMORPG server emulator in C++
A game server reimplementation for a certain turn-based anime game
Offline Yu-Gi-Oh! Master Duel
Minecraft Bedrock Edition server software in Java
Server for the MMORPG MU Online
MapleStory v83 private server emulator (archived)
Nintendo Wi-Fi Connection server emulator for DS and Wii games
Launcher that redirects Genshin Impact traffic to Grasscutter private servers
Docker scripts and installers to run classic MMO private servers offline on Steam Deck
Continued MaNGOS World of Warcraft Classic server emulator
Private server research project for a certain discontinued mobile game
World of Warcraft vanilla server emulator
Ragnarok Online server emulator
Progressive vanilla World of Warcraft server emulator for patches 1.2-1.12
Minecraft Bedrock Edition server software in Go
Final Fantasy XIV server emulator (4.0+) in C++
Dark Souls 3 and Dark Souls 2 private server emulator
LEGO Universe server emulator
Ultima Online server emulator in C#
Web server and launcher for offline/LAN multiplayer in Age of Empires titles
Server replacement for the HITMAN World of Assassination trilogy
Server emulator for the defunct MMORPG WildStar
OpenTibia server emulator for modern Tibia protocol versions
Player vs Player Gaming Network: Battle.net and Westwood Online server emulator
EverQuest server emulator
Minecraft Java server implemented in Node.js
Private server for the rhythm game Arcaea
A private server for some anime game
Server emulator for Marvel Heroes
World of Warcraft 3.3.5 server emulator (C(ontinued)-MaNGOS)
World of Warcraft 2.4.3 server emulator (C(ontinued)-MaNGOS)
Final Fantasy XI server emulator
一个微型的 Arcaea 本地服务器 A small local server for Arcaea
Private server for Geometry Dash
Modern C# MMORPG server emulator for an OpenTibia-style client
Pokemon GO server emulator
Open-source server emulator for the Mario Royale browser game
Deprecated Final Fantasy XI server emulator
Club Penguin private server written in Python 3
Server emulator for RuneScape 2 as it was in 2004
Knight Online server and client reimplementation project
High-performance Ultima Online server emulator in C#
Asheron's Call server emulator
Java server reviving Habbo Hotel v14 (2007 era)
RuneScape 2004-era server emulator
Standalone Game Sync server emulator for Pokémon Black & White
Open-source MMORPG server emulator (Tree of Savior)
Server emulator for a mobile pinball game.
A private osu! server for everyone. Simpler than Akatsuki's production stack, while maintaining core functionality, p...
Phantasy Star Online game server, proxy and reverse-engineering tools
Monster Hunter Frontier server emulator in Go
Dark and Darker private server implementation in Python
PSN-compatible server used by RPCS3 for online play
Hobby game services network for Konami Bemani arcade games
Classic Ultima Online server emulator in C#
Multiplayer private server for Beat Saber with PC and Quest crossplay
Minecraft Classic protocol server software
Payday 3 server emulator
Open-source Toontown Online based on the final Disney client version
Reverse engineered Minecraft server implementation (1.4.x protocol)
RuneScape private server suite in Java
Old School RuneScape game server emulator
GameSpy replacement backend services (master server, NAT negotiation, presence)
Star Wars Galaxies pre-CU server emulator core
Local single-user Fortnite backend server emulator
Server emulator for MapleStory 2
Server emulator for Need for Speed (2015) for custom servers and offline play
Python Brawl Stars server emulator for v26
High-performance Minecraft Java Edition server implementation
A server software implementation, ineroperable with a certain anime game client. The code in this repository is fully...
Aion server emulator
Open server and utilities for Cube World
Final Fantasy XI server emulator
World of Warcraft 2.4.3 server emulator
Reimplementation of vanilla Minecraft features on Minestom
Fortnite backend emulator with matchmaking and XMPP support
Lineage II Interlude server emulator in C#
Open-source GameSpy backend emulator
Server emulator for Dragalia Lost
Demon's Souls private server emulator
C# MU Online server supporting multiple client versions
PenUltima Online server compatible with most Ultima Online clients
Quest mod that connects Beat Saber to BeatTogether multiplayer servers
A server emulator for the game Stella Sora
Dark Age of Camelot server emulator
The Server project for SPT
Nintendo Wi-Fi Connection replacement server by WiiLink
Unofficial Final Fantasy XIV server emulator for 7.x
Project Dollhouse, a reimplementation of The Sims Online client and server
Reimplementation of a server for Azur Lane
MapleStory v95 server emulator in C#
Reverse engineering and reviving the mobile game Zombie Cafe
Final Fantasy XIV v1.23b server emulator
BaPs
Metin2 open source server emulator in C#
Replacement Nintendo Network account server for Wii U and 3DS
Dedicated servers for Plants vs. Zombies: Garden Warfare 1, 2 and Battle for Neighborville
EVE Online server emulator in C#
Private server for Plants vs. Zombies Garden Warfare 1, 2 and Battle for Neighborville
Open source MapleStory v83 server emulator
MapleStory v95 server emulator
e-amusement server emulator for Dance Dance Revolution A
Server emulation for The Cycle: Frontier
Revival of Disney's Pirates of the Caribbean Online with a rewritten server
Community reimplementation of the Rec Room servers
Punishing: Gray Raven private server!
RuneScape Classic private server emulator
Need for Speed: World server emulator core
Node.js Lineage 2 server emulator (Chronicle 1)
Ultima Online server emulator
A C# rewrite of the SPT server project.
SharpMC, a Minecraft server written in C#
Reimplementation of the Minecraft server in pure Rust
Experimental S4 League server emulator
Offline restoration project for a discontinued mobile game
Ultima Offline eXperiment 3 Ultima Online server emulator
Pretendo's Miiverse replacement service for Wii U and 3DS
Server reimplementation for Wangan Midnight Maximum Tune 6
Dragon Ball Online Global client and server emulator
Emulated server for Hitman: Absolution and Hitman: Sniper Challenge
Unofficial local game emulation server for Hoshimi
Free Dark Age of Camelot server emulator
Warcraft III loader that connects the game to PvPGN Battle.net servers
A server software reimplementation for an old version of a certain anime game about factories.
Server emulator for the shut-down MMO The Matrix Online
Online server emulator for NFS Most Wanted, Underground 2 and Carbon
Private server emulator for Brawl Stars v24 in C#
DragonFable private server emulator for the current client
RuneScape Classic web client
Reverse engineered server for Card Wars Kingdom
Cabal Online server emulator
Server emulator for Yo-kai Watch Puni Puni
Open-source multiplayer game server compatible with the RuneScape client
A private server that supports all osu! clients (2007-2026)
Zenless Zone Zero server emulator focused on efficiency, stability and correctness.
Minecraft Beta 1.7.3 compatible server written in C++
HTML5 Habbo Hotel package with server, client and CMS
Server emulator for Final Fantasy XI
Minecraft server implementation in C++
Server for Pokemon Dream World
Server emulator for Final Fantasy XIV (Stormblood 4.10)
C# server emulator for The Matrix Online
Free Infantry Online server emulator
Server Emulator for a certain NTR game
A very functionally incomplete World of Warcraft: Wrath of the Lich King server emulator written in pure rust.
Star Wars Galaxies server emulator for the JVM
🌅 Sunrise - osu! server written in C#
Server emulator for MapleStory 2
Python Brawl Stars server emulator for version 28.189
From-scratch reimplementation of the Knight Online game server and client
Reimplementation of the Metal Gear Solid V: The Phantom Pain backend server
Elden Ring custom matchmaking server implementation
OpenBachelorS
Revival server for Xbox Live 1.0
Open-source reimplementation of the ProTanki server
A WIP Spore Server Replacement
Server reimplementation for Myst Online: Uru Live (D'ni in Real-Time Server)
Clean-room reimplementation of the Photon LoadBalancing server
Mass Effect 3 EA Blaze server emulator for LAN and WAN play
An osu!(lazer) private server that is easy to deploy, highly scalable, and fully featured to meet diverse operational...
High-performance osu! Bancho server re-implementation in C++
An experimental World of Warcraft emulator in Rust
Minecraft Classic server software written in Python
Unofficial local compatibility server and profile editor for Pokémon TCG Pocket
World of Warcraft server emulator written in Go
A 2006 RuneScape 2 Emulation Server.
EVE Online server emulator for the Crucible client
Research report on reconstructing the archived Destiny 2 build 86657 client (Sunrise/Dawn)
Open-source reimplementation of the Wiimmfi payload for Mario Kart Wii
a server software re-implementaion for R1999
Server that emulates Classic Battle.net for Diablo, StarCraft and Warcraft II/III
EA Blaze server emulator for Battlefield 3
DoctoratePy
Clean-room server emulator for the shut-down arena shooter Batla 3D
A Dragalia Lost Private Server
Habbo Hotel emulator for the 2001 v1 client
WIP Rust server for WoW 1.12
Habbo Hotel server for the Flash production client
Decompilation of Fortnite Alpha (2016) game server logic
server for that one card game
Habbo Hotel R39 server emulator
Server sofware reimplementation for an old version of a certain anime game
Educational Diablo III game server emulator
开放空间/OverField 服务端部分实现
Habbo Hotel emulation server
Assetto Corsa Competizione server
Habbo Hotel v31 private server in Kotlin
An open source server for the defunct 2015 mobile game Sonic Runners.
VirtueOS, an Old School RuneScape private server
Reverse-engineered Blaze server for Plants vs Zombies: Garden Warfare 2
Server emulator for the Diablo 3 beta client
Open-source private server for Hay Day 1.5.42
Private server for Blue Archive (Steam)
overfield emu server
OpenLethe
Rewritten SharpMC Minecraft Java Edition 1.11 server in C#
Battlefield 3 LAN server emulator
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Open-source server reimplementation for an early version of an anime game with stars and rails
Reverse-engineered multiplayer private server for the PS2 game Mystic Nights
A sif2 server
Conquer Online private server skeleton
Myst Online: Uru Live server written in Rust
Reverse-engineered UberStrike client and server
Habbo Hotel emulator in C# .NET 4.0
C++ reconstruction of Silkroad Online's SR_GameServer
Habbo Hotel emulator for the V9 protocol, based on Kepler
Private server for the shut-down mobile game Pangya Mobile
C# reconstruction of d2dbs, the Diablo II database server from bnetd/PvPGN
server for a random 2d game
World of Warcraft authentication server for development
Open-source 2009-era RuneScape server remake
A custom, completely from-scratch open source server emulator for Asheron’s Call built on C#.
Unofficial Myth War I server and tools
Server and client framework that recreates RuneScape Classic
Game server reimplementation for Umamusume (global region)
Server for Blacklight: Retribution 3.02 based on the decompiled ZCure library