Tsunami

Choose a point within range; a wall of water up to 300 feet long, 300 feet high, and 50 feet thick springs into existence there and remains for the duration of the spell.

When it appears, each creature in the wall’s area must make a Strength saving throw, taking 6d10 bludgeoning damage on a failure, or half as much on a success.

The wall moves 50 feet away from you at the start of each of your turns after it appears, along with any creature caught in its area. Huge or smaller creatures within the space the wall moves through must make a Strength saving throw or take 5d10 bludgeoning damage. Creatures can take this damage only once per round. At the end of the turn, the wall’s height is reduced by 50 feet, and the damage creatures take from this spell on subsequent rounds is reduced by 1d10. When the wall reaches a height of 0 feet, the spell ends.

Creatures struck by the wall can try to swim free, but the force of the wave requires an Athletics check against the spell’s DC to move. On a failure, they can’t move. Creatures that move out of the spell’s area fall to the ground.