Hmmm, Ricin.:hmm:
Interesting choice. Somewhat impractical, but it gets the job done. Easy to harvest, but hard to produce. It is a CDC Class "A" agent, which are the most deadly Chemical/Biological weapons on Earth. Among other Class "A" agents are Botulinium (Botulism), the 1918 Influenza A Virus (VERY deadly flu), Anthrax, and Salmonella. The Ricin substance is harvested from the castor bean, a very popular seed from the Castor Plant. The bean itself is easy to find, them being around many lakes and rivers here in Florida, and even in the schools around here. Ricin is the substance that is hardened into "beads" that are EXTREMELY hard to crack. You'll need something like a jackhammer to break it. It's deadly when inhaled, blocking the protein synthesis of your rRNA. As you might assume, I find this kind of stuff very interesting. Ask me for more information if you are confused.