Ice Knife
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.
Ice Knife 5.5e 2024 vs. 5e 2014 edition differences
The 2024 version clarifies that the explosion affects "the target and each creature within 5 feet of it" (instead of "point where the ice exploded"). The damage increase wording changes from "when you cast this spell using a spell slot of 2nd level or higher" to "the Cold damage increases by 1d6 for each spell slot level above 1," but mechanically they are equivalent.