Black Tentacles

Squirming, ebony tentacles fill a 20-foot square on 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 take 3d6 bludgeoning damage and be restrained by the tentacles until the spell ends. A creature that starts its turn in the area and is already restrained by the tentacles takes 3d6 bludgeoning damage.

A creature restrained by the tentacles can use its action to make a Strength or Dexterity check (its choice) against your spell save DC. On a success, it frees itself.

Squirming, ebony tentacles fill a 20-foot square on ground that you can see within range. For the duration, these tentacles turn the ground in that area into Difficult Terrain.

Each creature in that area makes a Strength saving throw. On a failed save, it takes 3d6 Bludgeoning damage, and it has the Restrained condition until the spell ends. A creature also makes that save if it enters the area or ends it turn there. A creature makes that save only once per turn.

A Restrained creature can take an action to make a Strength (Athletics) check against your spell save DC, ending the condition on itself on a success.