Unity - The multiplatform game creation tools for everyone.
Pygame - Pygame is a set of Python modules designed for writing games.
Godot Engine - Feature-packed 2D and 3D open source game engine.
GDevelop - GDevelop is an open-source game making software designed to be used by everyone.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
libtwo - All-purpose c++ app prototyping library, focused towards live graphical apps and games