Arcane Spear

You hurl a spear 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 expends one of its available, lowest-level spell slots as if the spell had been used. 

At Higher Levels. For each spell slot of 4th level or higher, the damage increases by 1d10. When you cast Arcane Spear using a spell slot of 6th level or higher, a successful hit expends two of the target's spell slots instead of one.