Godot is a powerful cross-platform game engine
The HTML5 Creation Engine
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
A game engine with an emphasis on real-time cutting-edge solutions
A refreshingly simple data-driven game engine built in Rust
A completely free, open-source, 2D game engine
A fresh & lightweight javascript game engine
High performance UI layout library in C
Amateur 3D Game Engine
Vivid3D is a C++ IDE/3D engine, with python scripting.
MIT Licensed Open Source version of Torque3D from GarageGames
Retro game engine for creating games like it's 1997
Vivid is a modern C++ 3D engine using OpenGL4+
Cross-platform 3D scene editor based on three.js, golang and mongodb
Improved version of the X-Ray Engine, the game engine
scriptable game engine with built-in support for 2D graphics and sound
Mahasona engine is an open source game engine.
BxEngine For Marmalade And QT
Advanced 2D/3D(CPU,GPU) Game Engine Library