The player places sonar devices at various places in the ocean to locate sunken treasure chests. Sonar is a technology that ships use to locate objects under the sea. The sonar devices (in this game) will tell the player how far away the closest treasure chest is, but not in what direction. But by placing multiple sonar devices down, the player can figure out where the treasure chest is. There are three chests to collect, but the player has only sixteen sonar devices to use to find them. Imagine that you could not see the treasure chest in the following picture. Because each sonar device can only find the distance, not direction, the possible places the treasure could be is anywhere in a square ring around the sonar device