Godot Engine - Feature-packed 2D and 3D open source game engine.
Project Anarchy - Project Anarchy is a complete end to end game engine and state-of-the-art toolset for mobile.
Unity - The multiplatform game creation tools for everyone.
Limon Engine - Limon is a multi platform 3D game engine mainly focusing on first person games.
Cocos Creator - Cocos Creator is more than a efficient, lightweight, free, open-source, cross-platform graphics engine: it's also a platform to create 3D content in real time.
GDevelop - GDevelop is an open-source game making software designed to be used by everyone.