Godot Engine - Feature-packed 2D and 3D open source game engine.
Unity - The multiplatform game creation tools for everyone.
GDevelop - GDevelop is an open-source game making software designed to be used by everyone.
Struckd - 3D Game Creator - Struckd is the next-generation gaming platform for user created content where people of all ages...
Construct 2 - Scirra Construct is a 2D game development engine with a focus on building games visually.
Reality Factory - Reality Factory is a free suite of game development tools for building 3D games.