The Ren'Py Visual Novel Engine
GZDoom is a feature centric port for all Doom engine games
s&box is a modern game engine, built on Valve's Source 2
05k0nz's legacy is safe
UZDoom is a feature centric port for all Doom engine games
Cross-platform, open source, and super fast MUD client with scripting
A free/open source client and automation tool for Ragnarok Online
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
3D Game engine with editor
Games you can play in your terminal written in go
Stride (formerly Xenko), a free and open-source cross-platform C# game
An updated version of the classic "Basic Computer Games" book
Skript is a Bukkit plugin which allows server admins
Complete Open Source and Modular solution for MMO
Free game engine for development of desktop, mobile, and web games
Multi Theft Auto is a game engine
Cocos simplifies game creation and distribution with Cocos Creator
A free mixin-based injection hacked client for Minecraft
Experimental menu for GTA 5: Enhanced
A completely free, open-source, 2D game engine
A Bee Swarm Simulator macro for Windows
Cross-platform 2D and 3D game engine with modular architecture
3D game engine/framework in C, with Luajit and Python bindings now
An OpenGL RTS game engine written in C
A lightweight game server framework implemented with Actor Model