Whisker's Dimensional Slap

You make a backhanded slap motion towards a creature in attempt to force them out of your sight for good. Choose a creature within range and make a ranged spell attack against it. On a hit, the creature must make a Charisma saving throw. On a failed save, it is transported to a random location on a random plane of existence. A creature transported this way first gains 3d6 temporary hit points, and then must find its own way back to your current plane of existence. After an hour, the target loses any remaining temporary hit points from this spell. On a success, the creature instead takes 3d6 force damage and is not transported.