NebulaNebula is an open-source and free-to-use modern C++ game engine.
EtlegacyET: Legacy is an open source project based on the code of Wolfenstein: Enemy Territory which was released in 2010 under the terms of the GPLv3 license.
Babylon.jsBabylon.js is a powerful, beautiful, simple, and open game and rendering engine packed into a friendly JavaScript framework.
LumberyardAmazon Lumberyard is a free AAA game engine deeply integrated with AWS and Twitch – with full source.
Jme CljA Clojure 3D Game Engine Wrapper, Powered By jMonkeyEngine
ArxlibertatisCross-platform port of Arx Fatalis, a first-person role-playing game
3dworld3D Procedural Game Engine Using OpenGL
Xray Oxygen🌀 Oxygen Engine 2.0. [Preview] Discord: https://discord.gg/P3aMf66
Etlegacy DeprecatedArchived repository. For current repo, see: https://github.com/etlegacy/etlegacy
ZooshiMulti-platform game where you feed well dressed animals with sushi
QfusionSource code for cross-platform OpenGL gaming engine
inanityCross-platform C++ game engine.
PiEA simple lightweight Game Engine built on SDL2 GLEW and (soon) OpenAL (currently using Port Audio instead). Written in C++
GroundEngineGround Engine is an easy to use Game Engine for 3D Game Development written in C++
ioq3The ioquake3 community effort to continue supporting/developing id's Quake III Arena