You create a shard of ice and fling it at one creature within range. Make a ranged spell attack against the target. On a hit, the target takes 1d10 Piercing damage. Hit or miss, the shard then explodes. The target and each creature within 5 feet of it must succeed on a Dexterity saving throw or take 2d6 Cold damage.
Using a Higher-Level Spell Slot
The Cold damage increases by 1d6 for each spell slot level above 1.