Arcane Smite

The target hit by the strike takes an extra 1d6 Force damage from the attack. Additionally, if they have a Spellcasting or Pact Magic feature, they lose an amount of spell slots that add up to the Force damage taken. If they can not, they take an additional 1d6 Force damage for every point of spell slots not given up.

If the target does not have a spellcasting feature, they instead have the choice of only an Action, Bonus Action, or Movement on their next turn, and cannot make more than one Attack action.

Using a Higher-Level Spell Slot. The damage increases by 2d6 for each spell slot level above 4.