Garry’s Mod 2

Game description:

Sandboxes come in a huge variety, and Garry’s Mod 2 is perhaps one of the most feature-packed of them. Rather than just creating a static environment, even though beautiful and complex, you can come up with a fully interactive setting where all the characters and objects will be interacting in a great number of ways! The menu contains all kinds of elements and instruments you need for that. You can also benefit from those already made by other players. Have fun!