Vilethorn

You create a mass of thorny acidic vines. The vines are made up of 5 foot cubic segments feet wide. The first segment grows at a point within 5 feet of you, and then 15 more segments instantly grows at any points you choose that are adjacent to another segment.

When the wall appears, each creature within its area must make a Dexterity saving throw. On a failed save, a creature takes 2d8 acid damage and starts its next turn with 15 less feet of movement, or half as much damage and no movement penalty on a successful save.

Whenever a creature ends its turn in the thorns, or moves into the thorns first the first time on its turn, it must make the saving throw or suffer the effects again.

The thorns are difficult terrain.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d8 for each slot level above 3rd.