Solar2D Game Engine main repository (ex Corona SDK)
Flax Engine, multi-platform 3D game engine
Cross-platform 2D and 3D game engine with modular architecture
Multi-platform 2D and 3D game engine
Cocos simplifies game creation and distribution with Cocos Creator
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
A game engine with an emphasis on real-time cutting-edge solutions
Cross-Platform C++ 2D/3D game engine
Powerful, mature open-source cross-platform game engine for Python
Injectable LUA scripting system, SDK generator, live property editor
GemRB is a portable open-source implementation of the Infinity Engine
Open source clone of the Age of Empires II engine
Self-hosted game stream host for Moonlight
Multi Theft Auto is a game engine
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
Source code repository of the FreeOrion project
Recreation of the classic Grand Theft Auto III game executable
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
The fastest AI powered Aimbot
Descent 3 by Outrage Entertainment
3D Game engine with editor
fheroes2 is a recreation of Heroes of Might and Magic II game engine
The game engine for everyone
Voxel game-creation platform with easy modding and game creation
Free game engine for development of desktop, mobile, and web games