Thermal Void

You conjure a shard of ice in an empty space you can see that's within range. The shard of ice called forth is soo cold, that it instantly pulls all heat towards it creating a thermal void. Each creature within a 20-foot-radius sphere of the shard must make a Constitution saving throw. A target takes 6d6 cold damage, and is pulled 5 feat towards the center falling prone on a fail save, or half as much damage on a success. 

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.