The user can choose the number of units and the number of rats. A unit is defined as one main room in the middle that consists of one food bowl and four water bottles, that is surrounded by 12 smaller rooms that serve as sleeping areas for the rats.
The goal of the game is to have the mischief of rats survive for as long as possible. The user can specify the amount of units and rats to spawn. When the game starts, the user can individually drag the rats onto the maze, or drop all of them with a button. During the game time, the user can observe the rats, as well as drag and drop any of the rats in the maze. When all the rats are dead, the game ends, and a graph is shown of the total population compared to the number of rats that died over time.