The flexible game engine
Godot is a powerful cross-platform game engine
Solar2D Game Engine main repository (ex Corona SDK)
Fast and lightweight JavaScript game engine built on WebGL and glTF
Cocos simplifies game creation and distribution with Cocos Creator
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
Flax Engine, multi-platform 3D game engine
Cross-platform 2D and 3D game engine with modular architecture
A game engine with an emphasis on real-time cutting-edge solutions
Simple and light-weight 3D game engine
Multi-platform 2D and 3D game engine
An OpenGL RTS game engine written in C
Zig game engine & graphics toolkit
Xash3D FWGS engine
Game engine supporting many 3D/2D formats and graphic effects
A complete 3-D game development suite written in Java
Open source voxel game engine with support for survival and crafting
Unreal Engine Archives Explorer
N64 Game-Engine and Editor using libdragon & tiny3d
Multi Theft Auto is a game engine
LayaAir is an open-source 2D/3D engine
A game engine powered by python and panda3d
Cross-Platform C++ 2D/3D game engine
Zero Hour running natively on macOS, iPhone & iPad
An unofficial rules engine for the world's greatest card game