Godot Engine - Feature-packed 2D and 3D open source game engine.
Unity - The multiplatform game creation tools for everyone.
Unreal Engine - Unreal Engine 4 is a suite of integrated tools for game developers to design and build games, simulations, and visualizations.
BYOND - BYOND is the premier community for making and playing online multiplayer games.
Phaser - Desktop and Mobile HTML5 game framework. A fast, free and fun open source framework for Canvas and WebGL powered browser games.
Construct 2 - Scirra Construct is a 2D game development engine with a focus on building games visually.