"Poisonous Herbs" is a side quest available in Dying Light.
- Search the marked zone for poisonous herbs.
Wolf's bane can be found southwest of the tower, its location is marked on the map just like Herbs and Underwater Alge. Purple flowers, relatively tall.
"I need wolf's bane to poison blades. The weed is easily identifiable - violet flowers on long stems. They grow in the gullies on the west side of the district; sometimes along the streams. Obviously I have a reward for anyone who can deliver them to me."