Deep Purifier's Eldritch Strike

Invoking the Deep Purifier, you create a Large purple floating claw within range. The claw doesn't occupy its space. Make a melee spell attack against a target you can see within 5 feet of the claw. On a hit, the target takes 15d8 Force damage, and must make a Dexterity saving throw. On a failed save, the target receives a spectral wound if it does not have one, The wound last for 1 minute or until the target receives magical healing. A creature with a wound takes 1d6 Force damage at the start of each of its turns. As an action on a future turn, you can move the hand up to your Speed and make an attack with it.