Vine Wave

You send a wave of thorny vines to engulf an area in front of you.

Each creature in a 60 ft. Cone makes a Dexterity saving throw, taking 9d8 Piercing damage and having the Grappled condition (escape DC equals your spell save DC) for 1 minute on a failure, or half as much damage only on a success. A creature that is grappled by these vines takes 2d4 Piercing damage at the start of each of it's turns.

Using a Higher-Level Spell Slot. The damage increases by 1d8 and 1d4 per level of spell slot above 6.