Tithe

You call on a greater power to magically tax a creature in the process of casting a spell. The creature must succeed on a Wisdom saving throw or expend an additional spell slot of a level equal to or greater than the level of the spell it is casting.

If it cannot, or chooses not to expend the additional slot, its spell fails and has no effect.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the creature has disadvantage on its saving throw. When you cast this spell using a 9th level spell slot, the creature must choose to expend all of its remaining spell slots (must be at least 1) of a level equal to or greater than the level of the spell it is casting to avoid the negation effect.