Solar2D Game Engine main repository (ex Corona SDK)
Multi-platform 2D and 3D game engine
Cross-platform 2D and 3D game engine with modular architecture
Cross-Platform C++ 2D/3D game engine
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
Cocos simplifies game creation and distribution with Cocos Creator
A game engine with an emphasis on real-time cutting-edge solutions
Flax Engine, multi-platform 3D game engine
Powerful, mature open-source cross-platform game engine for Python
Open source clone of the Age of Empires II engine
GemRB is a portable open-source implementation of the Infinity Engine
N64 Game-Engine and Editor using libdragon & tiny3d
Self-hosted game stream host for Moonlight
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
Write your game with TypeScript in UE or Unity
Multi Theft Auto is a game engine
Recreation of the classic Grand Theft Auto III game executable
Descent 3 by Outrage Entertainment
Source code repository of the FreeOrion project
Voxel game-creation platform with easy modding and game creation
Voxel game engine in C++ with OpenGL
3D Game engine with editor
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
The game engine for everyone
fheroes2 is a recreation of Heroes of Might and Magic II game engine