Falling-sand game

A falling-sand game is a genre of video game and a sub-genre of sandbox games which typically utilize a two-dimensional particle or cellular automaton based game engine to simulate various materials interacting in a sandbox environment.

In falling-sand games, the user can interact with (e.g. place and remove) particles on a canvas which can interact with other particles in various ways, which can lead to complex emergent behaviour. As sandbox games, they generally have an emphasis on free-form gameplay, relaxed rules, and minimal goals.

Despite the name, falling-sand games typically contain a multitude of materials besides sand, often called "elements".