Vishkanya

The vishkanya, deadly and beautiful assassins, were developed in ancient India to end conflict between kings without widespread violence. According to the ancient literature, one way of grooming a girl was to dose her with poison a bit at a time, until she built up an immunity to it. She would then be sent into an enemy camp or tasked with getting close to a rival king, administering poison to him while being able to eat and drink from the same vessels to allay suspicion. In other cases, the girl might be purposely infected with a poison (spread through blood or sexual contact) or an infectious disease, before being dispatched to the rival capital or camp.