TrinityCore Open Source MMO Framework (master = 10.2.6.54499, 3.3.5 = 3.3.5a.12340, wotlk_classic = 3.4.3.54261, cata classic = 4.4.0.54027)

Unity3D Client And C# Server Framework

Complete Open Source and Modular solution for MMO

A MMOG engine of server.

#1 Open Source Unity Networking Library

最全面的游戏开发技术图谱。帮助游戏开发者们在已知问题上节省时间，省出更多的精力投入到更有创造性的工作中去。

A fast, scalable, distributed game server engine/framework for C++, include the actor library, network library, can be used as a real time multiplayer game engine ( MMO RPG/MOBA ), which support C#/Lua script/ Unity3d, Cocos2dx and plan to support Unreal.

rAthena is an open-source cross-platform MMORPG server.

一个基于Entity-Component模式的灵活、通用、可扩展的轻量战斗（技能）框架，配置可选使用ScriptableObject或是Excel表格. A flexible, generic, easy to extend, lightweight combat (skills) framework based on Entity-Component pattern. Configuration can choose to use ScriptableObject or Excel tables.

A free and open-source MMORPG server emulator written in C++

Framework to create an RPG or MMORPG (with the same code) in the browser with Typescript

游戏服务器框架，网络层分别用SocketAPI、Boost Asio、Libuv三种方式实现， 框架内使用共享内存，无锁队列，对象池，内存池来提高服务器性能。还包含一个不断完善的Unity 3D客户端，客户端含大量完整资源，坐骑，宠物，伙伴，装备, 这些均己实现上阵和穿戴, 并可进入副本战斗，多人玩法也己实现, 持续开发中。

A free/open source client and automation tool for Ragnarok Online

⚔️ An online JavaScript 2D Medieval RPG.

Hercules is a collaborative software development project revolving around the creation of a robust massively multiplayer online role playing game (MMORPG) server package. Written in C, the program is very versatile and provides NPCs, warps and modifications. The project is jointly managed by a group of volunteers located around the world as well…

This project aims to create an easy to use, extendable and customizable server for a MMORPG called "MU Online".

An Ultima Online server emulator written in C# .NET

An emulator for the defunct MMORPG WildStar which supports build 16042 (Final Patch)

Stendhal is a fun friendly and free multiplayer online adventure game with an old school feel.

Easy to use high performance Network library for Unity 3d