Dire Radiance

You cause a shaft of brilliant, cold starlight to lance down from above, bathing your foe in excruciating light. The nearer he moves toward you, the brighter and more deadly the light becomes. You target one creature within range, and do a spell attack. If hit, they take 1D6 radiant damage. If the target moves nearer to you on its next turn, it takes an extra 1d6 Radiant damage. 

At a higher level: This spell's damage increases by 1d6 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).