lua dev plugin for unreal engine 4 or 5
2D Game Engine
The imaginary eight-bit machine
A cross platform Lua based game engine
8-bit Graphical API for Java
Build Cross-platform Applications
3D .NET engine for Windows, Linux, Mac
Flexible and easy-to-use 2d game engine
Free strategy browsergame engine.
A generic 2D engine for any kind of game
Multi-threaded 2D Renderer licensed under the Mozilla Public License
Java game engine for shoot 'em ups, using Java2D.
AS3 Utilities library (Games Development Framework)
A cross-platform OpenGL based lightweight scenegraph library
Cross-platform 2D game engine
Tween for Torque
Make games with Lego-like building blocks