 Sthondat lymph extract significantly increases telepathic ability, but it is addictive, and is toxic with long use, causing muscle atrophy and thinning fur.The black-fur gene and the telepath gene are exclusive; no completely black-furred Kzin is telepathic, and all such cubs are taken by the Black Priests and raised within their cult.Telepaths are tolerated by the warrior class due to the specialized use of their skill, otherwise they endure a low-caste position in society, just above the status of slaves, with the occasional slave being considered of a higher social status.