Blade Cascade

You conjure ten magical blades in your space. They float in the air and orbit you for the spell’s duration. When you cast the spell — and as a bonus action on each of your turns thereafter — you can expend up to three blades, sending them streaking in a line 5ft wide and 30ft long. Each creature the blades pass through must make a Dexterity saving throw. A creature takes 2d6 Force damage per blade used on a failed save, or half as much damage on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, conjure one additional blade for each slot level above 4th.