Outer Essence Shard (Chaotic)

This flickering crystal holds the essence of an Outer 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 that property.

Property: Choose one creature who takes damage from the spell. That target has disadvantage on attack rolls and ability checks made before the start of your next turn.