Cyberix3D - Free online 3D Game Maker. Make your own 3D games online!
Unity - The multiplatform game creation tools for everyone.
Godot Engine - Feature-packed 2D and 3D open source game engine.
Open 3D Engine - Open 3D Engine is an open-source 3D game development engine in real-time.
Unreal Engine - Unreal Engine 4 is a suite of integrated tools for game developers to design and build games, simulations, and visualizations.
Phaser - Desktop and Mobile HTML5 game framework. A fast, free and fun open source framework for Canvas and WebGL powered browser games.