Clam Monster

You reach out your hand, and a ethereal clam bursts forth from it. When the clam reaches the target, the target must make a Dexterity saving throw. Large or larger creatures make this saving throw with advantage. The creature takes 5d8 bludgeoning damage and is grappled on a failed save, or half as much on a failed save, and is not grappled.

At higher levels: When you cast this spell at any level higher than 4th You can target an additional creature for every level after 4th