Beam of Virtue

You summon a 10-foot wide glowing white sigil under a single creature's feet. Moments later, a vertical pillar of burning light shoots up from the sigil. The pillar deals 3d6 radiant damage, dealing double damage to undead and evil creatures. All creatures within the sigil must succeed on a Dexterity saving throw or else they will be struck by the light.

At Higher Levels. When you cast this spell using a spell slot of 4th level and above, the damage increases by 1d6 and the sigil width increases by 5 ft for each slot level above 3rd.