Cocos Creator
Cocos is an open source development engine. It can be used to build games, apps and other cross platform GUI based interactive programs.
Dev
Open 3D Engine
Open 3D Engine
Stencyl
Make iOS (iPhone/iPad), Android, HTML5, Windows & Mac games without code using Stencyl.
Unreal Engine - The most powerful real-time 3D creation tool
Unreal Engine is the world’s most open and advanced real-time 3D creation platform for photoreal visuals and immersive experiences.
YoYo Games
GameMaker Studio 2 is the latest and greatest incarnation of GameMaker! It has everything you need to take your idea from concept to finished game. With no barriers to entry and powerful functionality, GameMaker Studio 2 is the ultimate 2D development environment!