Dancing Daggers

You conjure a cloud of daggers into existence and select one creature you can see for them to attack. The targeted creature takes 6d4 + 30 slashing damage at the start of each of its turns, or half damage with a successful Dexterity saving throw. The daggers follow the creature as it moves. If the creature teleports or moves to another plane, the daggers stay where they are and don’t follow. They attack only the creature they’re targeted against; others can walk through them without harm. 

As an action, you can redirect the daggers to attack another creature you can see within 100 feet of their current position.

The daggers disappear when the spell ends.