In chapter 7 of Fourth Wing, Violet mentions possessing a book of poisons. The art of mastering poisons has to do with the timing of administering.
- Fonilee berries: Can be found growing on a vine on oak trees. When ripe, the purple berries are tart and barely edible. When picked prematurely and left to dry, the berries are poisonous. Premature berries are a lavender color. The powder made from the dried berries is nearly white.
- Mushrooms (mentioned in chapter 7 of Fourth Wing)
- Leighorrel- This mushroom has hallucinogenic properties.
- Zihna root: Can cause feet to lose all feeling. Grows on one outcropping near the ravine.
- Tarsilla leaves: Can cause vision to turn blurry when consumed.
- Carmine tree bark: Can cause the consumer to feel sluggish and ill with an upset stomach.
- Walwyn fruit: When ingested raw, the consumer may have a hard time walking in a straight line.