Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
Voxel game-creation platform with easy modding and game creation
A retro game engine for Python
Fast and lightweight JavaScript game engine built on WebGL and glTF
A high-performance, industry-standard 2D physics engine built on Box2D
Godot is a powerful cross-platform game engine
The HTML5 Creation Engine
A 2D rigid body physics engine for the web
2D JavaScript Physics Engine
High performance UI layout library in C
Multi Theft Auto is a game engine
The Ren'Py Visual Novel Engine
The game engine for everyone
Open source voxel game engine with support for survival and crafting
A game engine powered by python and panda3d
A complete 3-D game development suite written in Java
Open-source engine for Heroes of Might and Magic III
fheroes2 is a recreation of Heroes of Might and Magic II game engine
Xash3D FWGS engine
Real Time Strategy game engine supporting early Westwood classics
Solar2D Game Engine main repository (ex Corona SDK)
Powerful, mature open-source cross-platform game engine for Python
The flexible game engine
dhewm 3 main repository
Descent 3 by Outrage Entertainment