Triple Rings of Light

You fire three rings of light in three lines, each 30 feet long and 5 feet wide. Each line points in a direction you choose.The end of each line must be within 30 feet of the end of one of the other lines. Each creature in a line must make a Dexterity saving throw. A creature takes 4d8 radiant damage on a failed save, or half as much on a successful one.
At the start of your next turn, the rings return to you, causing each creature in the line to make the same saving throw.
At Higher Levels.
When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d8 for each slot level above 3rd.