Arc blade

Evocation cantrip
Casting Time: 1 action
Range: Self (5-foot radius)
Components: V, M (a melee weapon)
Duration: Instantaneous
As part of the action used to cast this spell, you must
make a melee attack with a weapon against one
creature within the spell’s range, otherwise the spell
fails. On a hit, the target suffers the weapon attack’s
normal effects, except that any damage dealt by the
attack is lightning damage instead of its normal type.
Additionally, an arc of lightning jumps to a creature
you choose within 5 feet of the target, dealing 1d6
lightning damage.
This spell’s damage increases when you reach
certain levels. At 5th level, the melee attack deals
an additional 1d8 lightning damage and secondary
damage deals an additional 1d6 lightning damage to
their targets. Both damage rolls increase by one die
at 11th level (2d8 and 3d6), and 17th level (3d8 and
4d6).