Evard's Black Tentacles

{p/b} : Action : 90 Ft Range
Create 20 Ft Cube
Creates Difficult Terrain
DEX Save for creatures in the area on cast
3d6 bludgeoning damage & Restrain.
If restrained at beginning of turn take 3d6 bludgeoning
Each turn creatures can use their action to
make a STR or DEX to break the grapple.