Mongolian Brotherhood of Assassins

The Mongolian Assassins were the Brotherhood of Assassins located in and around.

When the leader of the Levantine Assassins, Altaïr Ibn-La'Ahad, his wife Maria and their son Darim traveled to the Mongol Empire to stop the Mongol leader Genghis Khan, the Mongolian Assassin Qulan Gal assisted the family. After making several plans, Qulan Gal and Altaïr infiltrated the Mongol camp in Xingging, near Xia province. However, Altaïr lost some of his skills in his old age and accidentally alerted the Mongols, being wounded in the process.

Qulan Gal was able to bring him to safety, and upon spotting Genghis Khan fleeing on horseback, Qulan Gal shot his horse with an arrow from his bow, allowing Darim to finish the Mongol leader with a final bolt from his crossbow.

Reference

 * Assassin's Creed: The Secret Crusade