Olive oil (Knowledge)

New berries
''On knotted-trunk trees grow small berries some pigs enjoy eating. That is, until someone took them all and squeezed them to get juice. They produced an oily liquid that tastes really nice with other foods, and that also has many other uses, such as a snout moisturizer, or to keep a pig's hair shiny. We should learn to cultivate these trees and how to efficiently press the berries to start producing more of this precious oil.''

Potential Requirements

 * You'll likely need Olives on the map for this to show up.