Dark Domination

Dark Domination: 

                                Lightning like arcs of dark energy springs from your finger tips. Drawn to itself, it forms a black sphere between your hands. As an action you may begin casting the spell. You may choose to make a ranged spell attack, on hit the target takes 1d8 necrotic damage. Alternatively you may choose to hold concentration. In doing so, you can then take sequential actions to boost the damage of the spell by your spellcasting modifier, you may only use this effect once per turn.

At Higher Levels:

When cast at higher levels, you may add and extra damage die per level. When cast at 7th level or higher the damage dice increase to a d10.