After the Battle of Kalka, the threat of a Mongol invasion of Rus’ passed. From now on, Russians and Mongols are friends. And now Mongol hordes are already riding farther west, while Russian regiments march behind them. What will be the response of knightly Europe? All of this, the wizard-mechanic Grigory Zaboutenny, who was transported here from the twenty-first century, will see with his own eyes.