If you’re curious about the software--or game development in general--consider picking up this Unity 2D Game Developer Bundle, which offers 15 hours of coursework for just $40.

Gravelbox is a 2D sandbox game made in Unity that allows you to make anything with the tools supplied to you. It was inspired by games like People Playground, Garry's Mod, And MaD2.

These days, one tool has essentially unlocked the world of game development for the masses. Since it was introduced in 2005, Unity has tried to make creating video games possible for everyone ...