Frigid blade

Evocation cantrip
Casting Time: 1 action
Range: Self (5-foot radius)
Components: V, M (melee weapon)
Duration: 1 round
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 attack does damage as normal,
except that the entire attack deals cold damage
instead of its normal type. Additionally, the target is
covered in a brittle frost until the start of your next
turn. If the target willingly moves before then, you
can use your reaction to deal 1d8 cold damage to the
target, ending the spell.
At 5th level, the melee attack and secondary
damage each deal an additional 1d8 cold damage.
Both damage rolls increase by 1d8 at 11th level
(2d8/3d8), and 17th level (3d8/4d8).