Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
Cocos simplifies game creation and distribution with Cocos Creator
A game engine with an emphasis on real-time cutting-edge solutions
MIT Licensed Open Source version of Torque3D from GarageGames
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
2D Game Engine with Lua Scripting made on top of SFML
A cross platform Lua based game engine
2D Game Engine, based on OpenGL and focused on Isometric Games
A simple WinAPI game engine