Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
3D and 2D game engine written in Rust
Cocos simplifies game creation and distribution with Cocos Creator
Free game engine for development of desktop, mobile, and web games
3D Game engine with editor
Cross-platform 2D and 3D game engine with modular architecture
Fast and lightweight JavaScript game engine built on WebGL and glTF
Stride (formerly Xenko), a free and open-source cross-platform C# game
MIT Licensed Open Source version of Torque3D from GarageGames
Cross-platform 3D scene editor based on three.js, golang and mongodb
3D C++ Game Engine - yet another open source game engine
Web powered cross-platform 3D, WebXR game engine
Visual Novel engine, editor and game development.
Zen3D is a 3D engine and editor for creating games