Weapon of the Day- Exceedingly Deadly

The Bubonic plague. So the mongols or tartars brought it to Europe through the siege of Feodossia. From thence, it is purported to have spread to Europe killing 20 or 30 or 40 million people. The bodies of those who had died of bubonic plague were routinely used to lob into besieged castles.

Biological war.

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