fheroes2 is a recreation of Heroes of Might and Magic II game engine
Injectable LUA scripting system, SDK generator, live property editor
Multi Theft Auto is a game engine
The game engine for everyone
Open source clone of the Age of Empires II engine
Powerful, mature open-source cross-platform game engine for Python
RPG Maker 2000/2003 and EasyRPG games interpreter
dhewm 3 main repository
3D Procedural Game Engine Using OpenGL
Solar2D Game Engine main repository (ex Corona SDK)
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
The flexible game engine
Cross-Platform C++ 2D/3D game engine
2D game development library for Ruby and C++
A multi core friendly rigid body physics and collision detection lib
Open-source engine for Heroes of Might and Magic III
Urho3D Game engine
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
Flax Engine, multi-platform 3D game engine
Animation Compression Library
Opensource crossplatform Fallout 2 game engine writen in C++ and SDL
GemRB is a portable open-source implementation of the Infinity Engine
Every creative journey starts with Unity Hub