lua dev plugin for unreal engine 4 or 5
Open Source MMORPG Framework
Desktop/Android/HTML5/iOS Java game development framework
OgreWin3D
Orx: Portable Game Engine
Updated emulator of Forgotten Realms: Unlimited Adventures
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
A 2D game engine and level editor
2D ARPG Engine
2D game engine for traditional platform games
Open Game Bootstrap
Single-/multi-player card game Mau Mau (similar to UNO®)
evolution for vegastrike SpaceSim/Combat/Trade game
Cross platform 2D/3D game engine written in C++11 & OpenGL ES 2/3
Cross-platform C framework very compact libraries and tools.
A generic 2D engine for any kind of game
3D Game engine
C++ game libraries plus server.
C++ Framework for slot machine games
A truly extensible cross-platform game engine
cross-platform 2d game engine