Elemental Essence Shard (Water)

This crackling crystal contains the essence of an elemental plane. As an action, you can attach the shard to a Tiny object (such as a weapon or a piece of jewelry) or detach it. It falls off if your attunement to it ends. You can use the shard as a spellcasting focus while you hold or wear it.

When you use a Metamagic option on a spell while you are holding or wearing the shard, you can use the following property:

You create a wave of water that bursts out from you in a 10-foot radius. Each creature of your choice that you can see in that area takes 2d6 Cold damage and must succeed on a Strength saving throw against your spell save DC or be pushed 10 feet away from you and fall Prone.