A simple poisoning wouldn't do, because due to their mutual suspicion of each other, they both ate from the same dishes prepared by the same cook. Furious that Stateira was taking her place in her son's affections, Parysatis hatched a plan to get her out of the way. Parysatis, mother of Persian King Artaxerxes II (435 or 445 BC-358 BCE), did not get along with her daughter-in-law Stateira. Gu could even kill from a distance, its malevolent spirit doing all the work with no need for actual poisoning.

Victims of gu poisoning were said to die vomiting blood or when all the food they ingested came back to life inside their stomachs. A supervenom could then be extracted from the beast and used to kill, cause disease, or create black magic love charms. They would eat each other until there was only one left, a creature now replete with the toxins of all its digested fellows. Gu was an ancient Chinese poison with magical properties that was said to have been created by enclosing multiple venomous animals such as snakes, lizards, scorpions, centipedes, and assorted insects in a box. Here are six legendary poisons, which may or may not have actually existed, and the one antidote to counter them all. The line between true crime and legend can be a blurry one, and in a time before toxicology tests and forensic pathology, stories of mysterious poisons with chameleon-like properties abounded.

Universal antidote for poisoning