Voxel game-creation platform with easy modding and game creation
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
The game engine for everyone
Solar2D Game Engine main repository (ex Corona SDK)
Multi-platform 2D and 3D game engine
Open-source engine for Heroes of Might and Magic III
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Cocos simplifies game creation and distribution with Cocos Creator
GemRB is a portable open-source implementation of the Infinity Engine
Orx: Portable Game Engine
Urho3D Game engine
Cross-platform 2D and 3D game engine
A cross-platform 2D game engine
Free and Open Game Programming Language for Windows and GNU/Linux
Real-time RPG for PC/tablet/phone; multiple quests and random dungeons
Blueshift is a cross-platform 3D game engine implemented in C++
Portable game engine with main focus on point-and-click adventures
The Atomic Game Engine is a multi-platform 2D and 3D engine
Open-source, cross-platform, C++ game engine for creating 2D/3D games
Paintown is a 2d fighting game engine.
Cross platform 2D/3D game engine written in C++11 & OpenGL ES 2/3
2D physics engine for games
3D Game engine