Electrify

You channel lightning into your hands. The next time
you hit a creature with a melee attack (including a
melee spell attack) before the start of your next turn,
the target takes 1d12 lightning damage and must make
a Constitution saving throw. On a failed save, the target
becomes shocked, stunning them until the start of
their next turn.

The spell ends after dealing damage, or at the start of
your next turn, whichever occurs first.

At Higher Levels. When you cast this spell using a
spell slot of 2nd level or higher, the damage increases
by 1d12 for each slot level above 1st.