RPG Maker 2000/2003 and EasyRPG games interpreter
Cross-Platform C++ 2D/3D game engine
JavaScript-based game engine designed to empower developers
The ioquake3 community effort to continue supporting/developing id's
Descent 3 by Outrage Entertainment
Open source library for creative expression on the web, desktop, etc.
dhewm 3 main repository
Fast and lightweight JavaScript game engine built on WebGL and glTF
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
A dead simple 2D game engine for Go
The Tiny JavaScript Game Engine That Can!
Go bindings for raylib, a simple and easy-to-use library
SDL based generic 2D game engine
A completely free, open-source, 2D game engine
A Tile-based Game Engine written in C# mimicing retro consoles.
Vivid is a modern C++ 3D engine using OpenGL4+
A hand-crafted 2D game library in Go
Go 3D Game Engine
3D C++ Game Engine - yet another open source game engine
Amazon Lumberyard is a free AAA game engine
mGSTEP port of the Cube game engine
2D Game Engine with Lua Scripting made on top of SFML
A 2d physics game engine for JavaFX
Open-source, cross-platform, C++ game engine for creating 2D/3D games
2d/3d Game Engine