Dimensional Slash

You brandish the weapon used in the spell's casting and unleash a slash, cutting through dimensions. Each creature in a 15ft cone must make a Constitution save. A creature takes force damage equal to the damage dice of the weapon used in the spell's casting + 4d6 force damage on a failure or half as much on a success.

This spell also affects creatures on the Border Ethereal.

At Higher Levels. When you cast this spell using a slot of 4th or higher, the damage increases by 1d6 for each slot above 3rd.