Godot Engine - Feature-packed 2D and 3D open source game engine.
Unity - The multiplatform game creation tools for everyone.
Cyberix3D - Free online 3D Game Maker. Make your own 3D games online!
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Open 3D Engine - Open 3D Engine is an open-source 3D game development engine in real-time.
GDevelop - GDevelop is an open-source game making software designed to be used by everyone.