Parlas

This grass, also called "herb of youth", visually and temporaly rejuvenates a subject. The parlas was once used to fight smallpox, but as the plant is becoming extremely hard to find, this use is no longer the main one. Be careful though, the parlas seems to be addictive on many creatures.
Drink an infusion of parlas rejuvenates in minutes the subject's appearance by 1d6 years for 8 hours. Then, slowly over the next 8 hours, this effect disappears and the subject returns to its true appearance.