Death Bolt

You launch a huge, dark bolt of lightning at a creature within range, forcing it to make a Dexterity saving throw. On a failed save, the target takes 1d8 necrotic damage, taking half damage on a success. In addition, on a failed save, the target absorbs the bolt, and the energy courses through it. At the start of each of its subsequent turns, it must succeed on a Constitution saving throw or take another 1d8 necrotic damage. On a success, the bolt is expelled and the spell ends.

On each of your turns for the duration of the spell, you can use a bonus action to send the bolt from the current target to a new target, forcing it to make the same Dexterity saving throw and subsequent Constitution saving throws.

At Higher Levels. If you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d8 and the DC for the Constitution saving throw increases by 1 for every level above 1st.