Clone feed

Clone feed was similar to amniotic fluid, but for Sontaran clones.

History
The Sontarans intended to use the ATMOS to fill the atmosphere of Earth with poisonous gas, which would become fuel for their new clones, and the planet would have become a clone world. However, the Tenth Doctor thwarted their plans by clearing the atmosphere. (TV: The Sontaran Stratagem/The Poison Sky)

Doctor Who: Legacy
In Doctor Who: Legacy, unarmed Sontarans use poisonous clone feed as a weapon against the player's characters, the Doctors and companions. The poison reduces health every turn but can be cured by certain characters. In the story, it is the Eleventh Doctor who alerts his company to the clone feed.