What am I still doing here? thought Ignatius Thorne. The city walls shook. The Mongol armies, under the command of General Subutai, were unleashing a relentless assault of colossal stones on Kaifeng, using their formidable trebuchets to sling the things through the air. Explosive bangs battered Ignatius’s eardrums. The explosions were followed by the acrid smell of that strange powder the Jurchen army was so fond of using. It was an unusual substance that Ignatius was convinced warranted...