Arcane Spear

You hurl a spear made of magical force at one creature within range. Make a ranged spell attack against the target. If it hits, the spear does 3d10 force damage. if the target is a spellcaster, the hit also wipes out one of its available, lowest-level spell slots as if the spell had been expended.  

At Higher Levels. For each spell slot used higher than 3rd level, damage increases by 1d10. When you cast arcane spear  using a spell slot of 6th level or higher, a hit also wipes out two of the targets spell slots instead of one.