The flexible game engine
Godot is a powerful cross-platform game engine
Solar2D Game Engine main repository (ex Corona SDK)
Cocos simplifies game creation and distribution with Cocos Creator
Flax Engine, multi-platform 3D game engine
Fast and lightweight JavaScript game engine built on WebGL and glTF
Cross-platform 2D and 3D game engine with modular architecture
Multi-platform 2D and 3D game engine
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
Cross-Platform C++ 2D/3D game engine
A game engine with an emphasis on real-time cutting-edge solutions
An OpenGL RTS game engine written in C
Xash3D FWGS engine
Zig game engine & graphics toolkit
Game engine supporting many 3D/2D formats and graphic effects
Open source voxel game engine with support for survival and crafting
A complete 3-D game development suite written in Java
Multi Theft Auto is a game engine
A game engine powered by python and panda3d
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
LayaAir is an open-source 2D/3D engine
A modular Common Lisp game engine
Recreation of the classic Grand Theft Auto III game executable
Descent 3 by Outrage Entertainment
A Flutter based game engine