Chromatic wave

A wave of chromatic energy sweeps out from you. You chose acid, cold, lightning, fire, poison, or thunder for the type of wave you create, Each creature in a 30-foot cube must make a constitution saving throw. On a failed save, a creature takes 8d8 damage of the type you chose and is pushed 20 feet away. On a successful save, the creature takes half as much damage and is not pushed. In addition, unsecured objects that are completely within the area of effect are automatically pushed 10 feet away from you by the spell's effect.