Dear Jonathan, 

Book 14, Chapter 1 of the Arthaśāstra provides recipes for poisons for killing enemies. One example: powder made from the speckled frog, Kauṇḍinyaka-insect  .... all this mixed with the sap of the Bhallāṭaka-tree ... causes instant death. The smoke of these products has the same effect. But where will you colleague find a speckled frog?

Best, Herman