But despite the Mongol's attempts to master siege warfare, the Chinese were still much more advanced in their military technology. They responded by filling bombs with crude oil, molten metal, chemicals and excrement.

Despite the ferocious bombardment, Genghis Khan ordered his men to advance to the walls. Once again, Chinese prisoners were in the front line.

As the city fell, the Chinese commander had just one option.

Genghis Khan was so confident of victory that he left his army to capture the city. His final command to his generals was to fulfill his prophecy. He ordered total annihilation.

molten: melted, liquefied by heat

excrement: waste discharged from the body, feces

annihilation: destruction, ruin; extinction, extermination