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