The Assassin Pill is a type of pill similar in appearance to a food pill or plasma pill and can easilly be mistaken as one by the untrained eye as there is a very subtle different. This difference varies with each type of assassination pill as there are many different types. For example, simple mixing in a poison even shinobi cannot detect into a food or plasma pill causes it to fall under the category of an assassin pill. However, it is difficult for most shinobi to create or use properly because if done wrong, is fairly easy to spote the differences between it and the pill it is trying to impersonate, ruining any possibility of getting away before being found out and because shinobi who carry food and or plasma pills will just as easily take it themselves thinking it to be one of those two, wasting it and their lives. Because of this, only a very small number of shinobi carry it, mostly the best assassins who can spot that subtle difference.