Sting

You target one creature you can see within range and inflict excruciating pain on a spot chosen by you. The target must make a CON saving throw and on a failed save if cast on the eyes, it causes Blindness until the end of their next turn. If cast on the tongue, it garbles speech. If cast on a hand, it ruins any precise manipulation of small objects, with a 1D4 (1 or 4) chance to drop them. All of these effects fade quickly and do no direct physical damage, but are enough to disrupt the casting of a spell if it spoils the Verbal, Somatic, or Material component of the spell being cast.