Youth Extension Infusion
From Creatures Wikia
This infusion COB was created by Spirit. It injects the chemicals aging and IV Antioxidant into the currently selected creature's bloodstream. When this is done at a life stage earlier than senior, it prolongs the amount of time your creature will spend in that particular life stage, and will extend their life overall, barring disease.
The Youth Extension Infusion uses NO C1 class numbers.