A fast and reliable entity component system (ECS) and much more
Cross-platform 2D and 3D game engine with modular architecture
Free game engine for development of desktop, mobile, and web games
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
A game engine with an emphasis on real-time cutting-edge solutions
Enigma is a puzzle game
Vivid is a modern C++ 3D engine using OpenGL4+
3D C++ Game Engine - yet another open source game engine
Amazon Lumberyard is a free AAA game engine
lightweight multi platform game engine
C++ Framework for slot machine games
OpenEstragon is a market economy simulator.
Cross-platform 2D game engine