Conjure Crescent blades

You conjure 5 3ft long crescent shaped blades that hover around you. You may cast this spell in a spell slot above the 5th and  get an extra blade for every spell slot above the 5th. (Attack)  You can use your bonus action to send one or two at any creature within range. The creature must make a dexterity saving throw or take 2d10 damage per blade or a quarter as much on a success. The blade breaks on impact. (Defense) you can use your reaction to send up to 5 blades at a target that is attacking you. The target takes 2d10 for each blade and the blades break on impact