Tide's Spear

You aberrate a large spear made of whirling water magic and throw it at a target. Make a ranged spell attack against a target within a 120 ft. range. The target of the attack roll takes 1d8 piercing damage. The spear then explodes in a tidal wave like explosion, each creature in a 20 foot radius sphere must make a Dexterity saving throw. On a failed save, the target takes an additional 4d10 bludgeoning damage and is knocked back 10 feet from the center. On a success, the target takes half damage and is not knocked back.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the cold damage increases by 1d10 for each slot level above 3rd.