Elemental Essence Shard (Ice)

Wondrous item, rare (requires attunement by a creature with Sorcery Points)

This roughly spherical shard, which is about 5 centimeters in diameter, is made out of ice-like aquamarine, and covered in sharp spikes in a manner that makes it resemble a star. As an action, you can attach the shard to a Tiny object (such as a wand, or a necklace) or detach it. It falls off if you 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:

Icy Grasp

A burst of cold energy emanates from one of your spell's targets in a 10-foot radius. Each creature in that area must make a Constitution saving throw. On a failed save, it takes 2d6 cold damage and is hindered by ice formations for a number of rounds equal to twice the cost of the Metamagic option used for this feature, or until it or another creature within reach of it uses an action to break away the ice. A creature hindered by ice has its speed reduced to 0. On a successful save, a creature takes half as much damage and isn't hindered by ice.