Cross-Platform C++ 2D/3D game engine
Open source clone of the Age of Empires II engine
Open-source engine for Heroes of Might and Magic III
Video game library manager with support for wide range of libraries
Powerful, mature open-source cross-platform game engine for Python
Flax Engine, multi-platform 3D game engine
Provides efficient allocation free async/await integration for Unity
The Open Toolkit library is a fast, low-level C# wrapper for OpenGL
dhewm 3 main repository
Accuracy-focused XNA4 reimplementation for open platforms
Gideros Release version
The flexible game engine
Galgame's Multilingual Real-time Machine Translation Tool
Questie: The WoW Classic quest helper
The source code to VVVVVV
A pure Go game engine
lua dev plugin for unreal engine 4 or 5
Mangos ZERO is a server for World of Warcraft
An open source reimplementation of the Among Us Server
3D Procedural Game Engine Using OpenGL
A .NET ascii/ansi console engine written in C# for MonoGame and XNA
A downloadable game for Windows, macOS, and Linux
Cross-platform, open source, and super fast MUD client with scripting
RPG Maker 2000/2003 and EasyRPG games interpreter
A charting and data visualization library for Unity