Cyrus’ Cutting Crystals

You create three long shards of ice in your space. They float around the air, facing where ever you look. As an action on each of your turns after casting the spell you can expend one or two of the shards, sending them to one or two creatures you can see within 90 feet of you. Make a spell attack roll for each shard flung in this way, on a hit the creature takes 2d6 cold damage. 

Alternately you can use your reaction when attacked to expend one shard and increase your AC by 3 against that attack only. Weather the attack hits or misses the shard is expended.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the amount of shards you create increase by one.