Witchweed - Old Empire

This spell creates a cloud of smoke that is utterly inhospitable to wizards. All wizards caught in this cloud cannot cast spells; they also suffer 2 points of damage per round they remain in the cloud. The cloud is stationary; once in place, it can be moved only by a gust of wind spell or equivalent.

The material component for this spell is burning tobacco (or some other noxious, fume-producing plant).