Aerithir's Wind Scythe

A solidified blade of air arcs out from your hands. Each creature in a 30-foot cone must make a Dexterity saving throw. On a failed save, a creature takes 6d8 slashing damage, is knocked prone, and has disadvantage on all attack rolls until  they make a successful Constitution or Wisdom save. On a successful save, the targets take no damage but are knocked prone and have disadvantage on their next attack roll.

A creature killed by this spell is decapitated.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d8 for each slot level above 5th.