You summon two spectral knights which hover nearby, ghostly swords drawn and ready for battle. For the duration of the spell, you can use a bonus action on your turn to command any number of the knights to attack a target within 5 feet of you. Make a melee spell attack for each attacking knight, dealing 3d8 force damage on a hit. Once a knight has successfully hit with an attack, it fades from existence. In addition, whenever you become the target of an attack, you can use your reaction to cause your knights to summon ghostly shields, protecting you from harm and granting you a bonus to AC against the triggering attack equal to the number of knights remaining. When you do so, one of the summoned knights fades from existence immediately after the attack. When the last summoned knight disappears, the spell automatically ends.
At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the number of knights you summon increases by one for every slot level above 4th.