Astral Nebula

You conjure a nebular cloud in a cube 5 feet on each side, centered on a point you choose within range. A creature takes 4d4 cold damage when it enters the spell’s area for the first time on a turn or starts its turn there. As a bonus action, you can choose to move to move the cloud anywhere within 30 feet of its current position.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 2d4 for each slot level above 2nd.