Open source clone of the Age of Empires II engine
Python MUD/MUX/MUSH/MU* development system
The Tiny JavaScript Game Engine That Can!
Full featured MUD server with all the trimmings.
Visual Basic 6 2D online adventure game engine
A free 3D game engine to create games and realtimes scenes for Windows
The multiplayer game engine
Retro game engine for creating games like it's 1997
Open source reimplementation of GTA San Andreas game engine in Unity
Python ctypes module for the Irrlicht Engine SDK
DOOM / Heretic / Hexen source port with enhanced graphics and UI
3D playground built on three.js and cannon.js
A fast, scalable, distributed game server engine/framework for C++
Planimeter Game Engine 2D - LÖVE-based game engine for Lua
Multiplayer game server based on Node.JS
Game engine for playing tomb raider 1 - 5 levels.
A mobile game distributed server implemented using netty4.X
A 2d physics game engine for JavaFX
online 4X browser game engine
2D game engine for traditional platform games
A C++ 3D game engine.
An online multiplayer turn based strategy game and board game engine.
Mahasona engine is an open source game engine.