Since the earliest days, humans have employed bioweapons both invisible and nefarious: killers on two legs, four, six, eight - and plenty with no legs at all. All of these agents of biological warfare, fresh with the fury of nature, have taken their turns inspiring terror in enemy forces, and turning the tide of unwinnable battles.
In the modern day, just as many bio-weapons have been employed by terrorists and monsters, "humans" who barely qualify for the title. Yes, history is filled with deadly organisms - viruses, bacteria, harmless looking flowers, and even playful sea mammals. All have seen their fair share of battle, and some were admittedly pretty awesome. But if this otherwise terrifying bioweapons list anything to teach, it may be that nature's most brutal creations are those dogs of war called "man."