Anyu's Floodgate (Arteria)

Surround yourself in a pool of raging water that hinders others from getting near. Dismiss the spell to trigger a flash flood that pushes creatures away 20 feet, dealing 6d4 Bludgeoning damage and knocking them Prone on a failed strength save. They only take half damage on a success.

Using a Higher-Level Spell Slot. The damage increases by 1d4 for each spell slot level above 4. Also increase the distance of the raging water and the flash flood by 10 feet.