Open source clone of the Age of Empires II engine
Python MUD/MUX/MUSH/MU* development system
Visual Basic 6 2D online adventure game engine
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
DOOM / Heretic / Hexen source port with enhanced graphics and UI
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
creator : Nikola Lukic about : Visual JS 2d canvas multiplatform game
2D game engine for traditional platform games
A C++ 3D game engine.
Java decentralized cross-platform network multiplayer game engine
Open Source 3D Game Engine
A retro style video game engine for RPGs and adventure games.
Java Client + JS/Canvas Server-Side System, with maintained Objects
Cross-platform 2D game engine