Rampant Wilds

Thorned vegetation erupts in a 5-meter radius centered on a point you can see and spreads. At the start of your turn, the area expands by 2 meters in all directions, to a maximum 15-meter radius. Creatures entering the area or starting their turn in it take 2d6 Piercing damage. You and your allies treat the area as normal terrain. As a Bonus Action on your turn, you may cause the briars in a 3-meter section to grasp - creatures in that section must succeed on a STR Save against your INT Check or become Immobilized until the start of your next turn.