Burrowing Bones

You cause a skeletal digit to streak forth towards a target you can see within range. The target takes 6d6 piercing damage, or half as much on a successful Dexterity saving throw. On a failed saving throw, the bony finger lodges itself into the victim's wound. The creature takes 2d6 necrotic damage at the beginning of each of its turns as the digit burrows through its body for the duration. The digit can be removed with a successful medicine check made against your spell save DC.