A development environment focused on modding
Solar2D Game Engine main repository (ex Corona SDK)
Godot is a powerful cross-platform game engine
Injectable LUA scripting system, SDK generator, live property editor
The flexible game engine
Fast and lightweight JavaScript game engine built on WebGL and glTF
Open Source real-time strategy game engine for early Westwood games
Flax Engine, multi-platform 3D game engine
Entitas is a super fast Entity Component System (ECS) Framework
Cross-Platform C++ 2D/3D game engine
Simple and light-weight 3D game engine
Simple Beat Saber Mod Installer
A free & open-source 2D sprite editor, made with the Godot Engine
Diablo build for modern operating systems
Sandbox video game with a powerful physics engine
An iOS & tvOS Frontend for Multiple Emulators
Magic Another Game Engine
Real Time Strategy game engine supporting early Westwood classics
Multi Theft Auto is a game engine
Open source voxel game engine with support for survival and crafting
GemRB is a portable open-source implementation of the Infinity Engine
fheroes2 is a recreation of Heroes of Might and Magic II game engine
A complete 3-D game development suite written in Java
Free, open source game engine online