Solar2D Game Engine main repository (ex Corona SDK)
Descent 3 by Outrage Entertainment
Free game engine for development of desktop, mobile, and web games
Flax Engine, multi-platform 3D game engine
dhewm 3 main repository
Recreation of the classic Grand Theft Auto III game executable
3D Game engine with editor
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Multi-platform 2D and 3D game engine
3D Procedural Game Engine Using OpenGL
Orx: Portable Game Engine
Modified source engine (2017) developed by valve and leaked in 2020
Multi Theft Auto is a game engine
Urho3D Game engine
Mini game engine for games104
A fork of dhewm3 with an emphasis on modernisation and vanilla Doom 3
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
3D C++ Game Engine - yet another open source game engine
Improved version of the X-Ray Engine, the game engine
A 2D game engine and level editor
KlayGE is a cross-platform open source game engine
A cross-platform 2D game engine
Game engine for playing tomb raider 1 - 5 levels.
scriptable game engine with built-in support for 2D graphics and sound
The Atomic Game Engine is a multi-platform 2D and 3D engine