Ethereal Missile

You create a purplish missile of magical force. The missile hits a creature of your choice that you can see within range, dealing 4d4 Force damage, or half damage on a successful Constitution saving throw. The missile extends into the Ethereal plane, damaging the target if it is on that plane. However, the spell itself doesn't grant the ability to see into the Ethereal Plane. You need to cast See Invisibility or use similar magic to target such a creature.  

Anything that prevents a target from taking damage from the Magic Missile spell also prevents it from taking damage from the ethereal missile.

Using a Higher-Level Spell Slot. The damage increases by 2d4 for each slot level above 1.