Writhing tentacles

Writhing, black tentacles fill a 20-foot square on the ground that you can see within range. For the duration, these tentacles turn the ground in the area into difficult terrain.

When a creature enters the affected area for the first time on a turn or starts its turn there, the creature must succeed on a Dexterity saving throw or be knocked prone by the tentacles. A creature that enters the area or starts is turn there takes 2d6 bludgeoning damage.

When you are standing in the area the tentacles move around you and heal you for half of the damage dealt.

At higher levels: When you cast this spell at 4th level or higher, the damage increases with 1d6 for every slot level above 3rd.