Open source clone of the Age of Empires II engine
Free, open source game engine online
Descent 3 by Outrage Entertainment
The Ren'Py Visual Novel Engine
Cross-platform 2D game engine focused on ultimate productivity
Open game and rendering engine packed into a JavaScript framework
Powerful, mature open-source cross-platform game engine for Python
A high-performance, industry-standard 2D physics engine built on Box2D
A refreshingly simple data-driven game engine built in Rust
3D Game engine with editor
A 2D rigid body physics engine for the web
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
New Godot bindings for Swift
Svelto ECS C# Entity Component System
Ct.js is a desktop game engine that makes learning programming fun
The Open Toolkit library is a fast, low-level C# wrapper for OpenGL
Python MUD/MUX/MUSH/MU* development system
2D game development library for Ruby and C++
Modified source engine (2017) developed by valve and leaked in 2020
A high speed C++17 Vulkan game engine
A hand-crafted 2D game library in Go
3D C++ Game Engine - yet another open source game engine
2D Game Engine with Lua Scripting made on top of SFML
A cross-platform 2D game engine
online 4X browser game engine