Blades of Olarune

You create a defensive arch of 5 arcane blades that hover above you for the duration. For every blade that hovers above you, you gain a stacking +1 to your Armor Class and to your Strength, Dexterity, and Wisdom saving throws. 

Whenever a hostile creature makes an attack roll against you or forces you to make a Strength, Dexterity, or Wisdom saving throw, one of the arcane blades are expended as it erupts and deals 1d6 + your spellcasting ability modifier in Force damage to the hostile creature. This spell ends early if all the blades are expended.

At Higher Levels. The spell creates one more blade for each slot level above 3.