Powerful, mature open-source cross-platform game engine for Python
Open source clone of the Age of Empires II engine
A retro game engine for Python
Pycraft is an open-source, OpenGL based game made in Python
3D game engine/framework in C, with Luajit and Python bindings now
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Free, open source game engine online
GemRB is a portable open-source implementation of the Infinity Engine
Vivid3D is a C++ IDE/3D engine, with python scripting.
A game engine for console based text games
DOOM / Heretic / Hexen source port with enhanced graphics and UI
Python ctypes module for the Irrlicht Engine SDK
KlayGE is a cross-platform open source game engine
The second demo of my game engine.
Text Based Game Engine and Parser
Open source, moddable game engine for the "Polygon Love 2" game
Tactical, turn-based game engine, that uses OpenGL and WinAPI
Scripting language of the hawk game engine