Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
Cross-Platform C++ 2D/3D game engine
Voxel game engine in C++ with OpenGL
Various things for PSX (PlayStation 1, PSone)
Flax Engine, multi-platform 3D game engine
Cross-platform 2D and 3D game engine with modular architecture
A modular Common Lisp game engine
Free game engine for development of desktop, mobile, and web games
UZDoom is a feature centric port for all Doom engine games
3D Procedural Game Engine Using OpenGL
Powerful, mature open-source cross-platform game engine for Python
Open game and rendering engine packed into a JavaScript framework
3D Engine c++
Stride (formerly Xenko), a free and open-source cross-platform C# game
Doom-based AI research platform for reinforcement learning
A charting and data visualization library for Unity
JavaScript-based game engine designed to empower developers
Go bindings for raylib, a simple and easy-to-use library
Gideros Release version
A game framework written with osu! in mind.
Cross-platform game engine in Rust
A free Chess program for Windows with a large set of features
Visual Basic 6 2D online adventure game engine
GLScene Engine for Delphi & C++Builder VCL Windows 32/64