Artic aura

For the duration you unleash a freezing aura. Any creature starting its turn within 20 feet of you must make a Constitution saving throw. On a failure, it takes 2d8 cold damage and its speed is reduced to 0 until the start of its next turn. On a success, a creature takes half as much damage and its speed halved.
As a bonus action on each of your turns for the duration, you can actively control the aura, excluding a number of creatures in the area up to your spellcasting modifier from the effects until the end of your next turn.
At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d8 for each slot level above 3rd.