The six forbidden cargoes of Leviathan biomechanoids were six specific items that were harmful for the living ships to transport. These included:
- Clorium - an element which could numb Leviathans and be used as an anesthetic for them.
- Novatrin Gas - a weaponized gas produced by the Plokavians, it could eat tissue from the inside out when inhales and was therefore incredibly destructive when inside Leviathans.
The six forbidden cargoes are derived from Farscape.