This piece of dead, white brain coral glistens with a myriad of colors when placed underwater. While holding this coral underwater, you can use an action to cause a beam of colored light to streak from the coral toward a creature you can see within 60 feet of you. The target must make a DC 17 Constitution saving throw. The beam's color determines its effects, as described below. Each color can be used only once. The coral regains the use of all of its colors at the next dawn if it is immersed in water for at least 1 hour.