Voxel game-creation platform with easy modding and game creation
The game engine for everyone
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
Solar2D Game Engine main repository (ex Corona SDK)
Cocos simplifies game creation and distribution with Cocos Creator
Open-source engine for Heroes of Might and Magic III
Multi-platform 2D and 3D game engine
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
GemRB is a portable open-source implementation of the Infinity Engine
Injectable LUA scripting system, SDK generator, live property editor
Orx: Portable Game Engine
2D game development library for Ruby and C++
Urho3D Game engine
a UCI chess engine
2D 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
scriptable game engine with built-in support for 2D graphics and sound
The Atomic Game Engine is a multi-platform 2D and 3D engine
Open-source, cross-platform, C++ game engine for creating 2D/3D games