C Dust

You imbue yourself with cold energy as you're body freezes over and make a ranged weapon attack If the target is a creature, it must succeed on a DC 15 Constitution saving throw or become frozen until the start of your next turn. Its speed is reduced by 10 feet it can take either an Action or a bonus Action on its turn, not both; and it can’t take reactions. (Extra Attack Applies Only Once per Turn). The attack/attack's gain (+2) to hit and does (2d8) additional cold damage.

At Higher Levels. This spell’s damage increases when you reach certain levels. At 5th (3d8) At 9th (4d8) At 13th (5d8) At 17th (6d8).