Witch Bolt (revised)
Casting Time: 1 action
Range: 30 feet
Components: V, S, M (a twig from a tree that has been struck by lightning)
Duration: Concentration, up to 1 minute
A beam of crackling blue energy lances out toward a creature within range, forming a sustained arc of lightning between you and the target. A creature must make a Dexterity saving throw. If the save is failed, it takes 1d12 lightning damage and your arc establishes a conduit between you and the target. If the save succeed, the creature only takes half the damage.
On each of your subsequent turns, you can use your action to shock a target you have established a conduit with, provided the target is within 30 feet of you. Your target takes 1d12 lightning damage. A creature must make a Constitution saving throw, and on a successful save, it takes no damage but doesn’t break the conduit.
Your conduit breaks if the target is ever more than 120 feet from you or if it has total cover from you.
At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, you increase the initial damage dealt to the target by 1d12 for each slot level above 1st, and the damage from your conduit by 1d12 for every two slot levels above 1st.