Elemental Shroud

You conjure spirits from the Elemental Planes that flit around you for the spell's duration. Until the spell ends, any attack you make deals an extra 2d8 damage when you hit a creature in a 15-foot Emanation. This damage is Acid, Cold, Fire, or Lightning (your choice when you make the attack).

In addition, any creature of your choice that you can see is considered to be in Difficult Terrain while in the Emanation.

Using a Higher-Level Spell Slot. The damage increases by 1d8 for every two slot levels above 4rd.