Crushing Depths

You impose the pressure of the deep sea on a creature you can see within range. The target must succeed on a Strength saving throw or take 8d6 bludgeoning damage and become blinded and restrained fro the duration. At the end of each of its turns the target can repeat the saving throw, on a success the spell ends.The target has advantage on the saving throw if it has a swimming speed and automatically succeeds if it is immune to the effects of being underwater at a depth greater than 100ft

At higher levels : When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d8 for each slot above 4th.