Solar2D Game Engine main repository (ex Corona SDK)
Multi Theft Auto is a game engine
Free game engine for development of desktop, mobile, and web games
Flax Engine, multi-platform 3D game engine
dhewm 3 main repository
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Descent 3 by Outrage Entertainment
Recreation of the classic Grand Theft Auto III game executable
Powerful, mature open-source cross-platform game engine for Python
Multi-platform 2D and 3D game engine
3D Game engine with editor
Open-source engine for Heroes of Might and Magic III
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
fheroes2 is a recreation of Heroes of Might and Magic II game engine
Voxel game-creation platform with easy modding and game creation
The game engine for everyone
3D Procedural Game Engine Using OpenGL
Open source clone of the Age of Empires II engine
Cross-Platform C++ 2D/3D game engine
Cocos simplifies game creation and distribution with Cocos Creator
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
A multi core friendly rigid body physics and collision detection lib
A game engine with an emphasis on real-time cutting-edge solutions
3D game engine with lua scripting
Cross-platform 2D and 3D game engine with modular architecture