The Cult of Shadow Tattoo is not merely a form of identifying members of the Cult of Shadow, it also serves a hidden and more sinister purpose. The ink used in the tattoo is actually a derivative of Sith Poison designed to more easily bring out and amplify the emotions that contribute to the Dark Side while dampening the ones most associated with the Light Side. The poison within the ink is self-perpetuating, meaning that its effect never lessens over time.