Echo of the Butterfly

You empower your Sword with the force of the wind, a soft whisper being the only echo of the strength behind this attack.. The cut creates small illusions of Butterflies, flying away from the Blade.

You brandish the weapon used in the spell’s casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the weapon attack’s normal effects. On the target's next action, movement, reaction, or bonus action within a round, the wound tears open, causing the target to suffer 1d4 weapon damage. Additionally, the target must make a Constitution saving throw (spell save DC) or be interrupted in the action that triggered the damage. However, they can still perform other unused actions normally afterward.

At Higher Levels. At 5th level, the meele attack deals an extra 1d6 weapons damage to the target, and the save DC increases by 1. The damage roll increase by 1d6 att 11th level (2d6) and again at 17th level (3d6)