Air-Cutting Blade

You infuse a whirling wind on a weapon you touch. Until the spell ends, the weapon you touch gains the reach property.

Once before the spell ends, you can forgo one of your attacks to release a cutting wave. A line of cutting wind 15 feet long and 5 feet wide emanates from you in a direction you choose. Each creature in the line must make a Dexterity saving throw or take 1d8 slashing damage on a failed save or half as much on a success.

At higher level: When you cast this spell using a spell slot of 2nd level or higher the damage increases by 1d8 for each slot level above 1st.