Cutting of the Weave

You attempt to cut the weave of a caster in the process of channeling. You can choose what level of spell slot this will expend at the time of casting. You have to beat the caster's spell save DC to succeed. On a critical success, you are able to counter attack with a cantrip. On a critical failure, you take 1d6 force damage from the mental strain and leave yourself vulnerable (disadvantage on saves) on any weaves cast by the opposing caster until the start of your next turn.

At Lower Levels. When you cast this spell at a lower level than the spell you are intending to cut, you have disadvantage on the roll.

At Higher Levels. When you cast this spell at a higher level than the spell you are intending to cut, you have advantage on the roll.