4th-level conjuration
Casting Time 1 action
Range 90 feet
Components V S M (Tentacle of giant octopus/squid)
Duration Conc. Up to 1 minute

For the duration, tentacles fill a 20-foot square on ground that you can see and turn it into difficult terrain.

When a creature enters the area for the first time or starts its turn there, it must pass a Dexterity save or take 3d6 bludgeoning damage and be restrained until the spell ends. If it's already restrained by the tentacles, it takes 3d6 bludgeoning damage.

The restrained creature can use its action to make a Strength or Dexterity check of its choice. On a success, it's freed.