Reverberate 2014

You touch the ground at your feet with the metal ring, creating an impact that shakes the earth ahead of you. Creatures and unattended objects touching the ground in a 15-foot cone emanating from you take 4d6 thunder damage, and creatures fall prone; a creature that makes a successful Dexterity saving throw takes half the damage and does not fall prone.

When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d6 for each slot level above 2nd.