Cat (potion)



"Cat is said to have been the first potion created specifically for witchers. The concoction allows witchers to pursue monsters into their lairs, including dark caves, ruins and crypts, because it augments vision to pick up additional wavelengths of light. To prevent blinding, the imbiber's pupils automatically narrow when in bright light. This is possibly the potion most commonly used by witchers."

The Cat potion grants vision in total darkness, a very handy ability in crypts and caves, or just badly lit interiors.

Source

 * Triss gives this formula at the end of the Prologue when Geralt asks her about the sorcerer who attacked the lab.
 * The Book of the Swallow
 * Receiving this potion from the druids in Act V, during "The Green March" will unlock the formula if you did not have it already.

Trivia

 * Cat is quite possibly the potion referred to in the Alchemy section of the in-game journal entry for Witchman.