Mordenkainen's Lost Notebook

Arcane Turmoil

2-level Abjuration

Choose a creature you can see within range. That creature must make a Wisdom saving throw. On a success, the spell has no effect. On a failure, the target loses 1 spell slot from the highest-level spell slots remaining to it, as if it had been used to cast a spell. For example, if the target has 4 1st-level spell slots, 2 2ndlevel spell slots, and 1 3rd-level spell slot when it fails its saving throw, it loses its 3rd-level spell slot.
 
At higher levels: When you cast arcane turmoil using a spell slot of 3rd level or higher, the target loses another of its highest-level spell slots for each slot level above 2nd you use to cast arcane turmoil.